The villains and characters people hate are usual my favorite characters
Try to establish them as horrible within their first scenes. For instance, at the start of my story, the antagonist keeps making flippant remarks about the protagonist's family and home to her face -- and he's supposed to be her husband-to-be. (Oh, and the cherry on top is he backhands one of her family's maids simply because the maid had bumped into him.)
So yeah, my antagonist's a dick. (And he gets his comeuppance at the end.)
I tend to think villains should be more complicated and sympathetic because the bad guys in real life seem so one dimensional and simplistic
I'm always really bad at this? Whenever I make a villain, I always want to put more details into their character to make them more 3 dimensional, but this usually ends up making them more sympathetic.
Heck, the one time I am trying to make a hateable villain, I found myself liking him more and more, to the point where I deliberately want to see if I can redeem him down the road without undoing anything he's done. I can't get myself to write these super-evil folks, no matter how useful it is.
The trick is in giving them just one, maybe one redeeming quality, just enough that some crazed folks might suggest they are doing things for the right reasons... And then, simultaneously, to give these characters the upper hand in almost every situation until they finally get their comeuppance.
If you go overboard with the evil, you just make a cardboard cutout and ironically that makes the tension fall back down. Think any action movie where the villain is some generic violent Russian mobster whose first appearance is them killing their own henchman. In contrast, think of Die Hard, the ultimate action movie, and remember just how FUN it is to hate Hans Gruber, who is a charming, twisted, evil man but doesn't have much in the way of evil stereotypes (e.g. bigotry, killing own henchmen, any kind of ideology).
I don't always write straight up bad guys or villains, but when I do, I use a ...I'll call it a technique.
"Twisting Logic"
It's not a perfect name, but for now that's what I'll call it. Basically everyone has an understanding of things like right and wrong. But to make a bad guy a bad guy, you don't have to make them evil, you just have to make them think differently.
The good guy in the story may think murder is bad, and that's a popular opinion, but the bad guy sees murder as an easy way to deal with problems. The bad guy wants to help just as much as the good guy. The bad guy thinks it's easier to kill off people who are trouble rather than capturing them. He knows it's cheaper, faster, and less work. But it goes against the norm.
But then you can build on this. If the bad guy thinks it's better to kill people, then who's to say he wouldn't also find pleasure in doing so. To him it could be like a video game, or any other pass time. It would become an action without shame.
I'm probably not explaining this as best I could but basically, you find some form of logic or social norm and then you break or twist it. And from there you play out the new logic chain until you have something that's believable but different from what most people typically accept.
27 days later
!!! this !!!!
i have two understandings of a "deliberately hateable" character. one is a textbook villain: arrogant, vengeful, oppressive, any trait that would symbolise the standard evil. more often than not they're made out to be ugly, or have some kind of defect that eventually becomes their representation as a character. these characters can be described as out of touch with their humanity. but that, to me, only gives more room for redemption.
the second one is simply just an antagonist: someone who's not necessarily aligned with evil (or could be), but doesn't agree to the protagonist's agendas. these people can have all the textbook villain traits but are designed in a way that's more complex, because they would be the ones who are purposeful with their intentions and therefore will not have that redemption arc.
and by redemption, i mean in the sense that they learn to become more humane. the stepping stone to that is acknowledgement, which the antagonist has already abandoned as i've said (i'm gonna be honest, i find these type of characters attractive more than textbook villains).
what i want to say here is that substance is my favourite thing in a villain, because it gets me to the point of wanting to ruin it all for them in the end.
I have two characters in my story that I kind of wasnt sure about. People would either hate them or love them. To my surprise, one character is greatly adored by my proofreaders over the other. One is close to a mafia boss and the other is an impulsive man with an easily bruised ego
I have not written a deliberately hateful character for my own purposes yet--as in, an original character, but I have written one for a fanfic. This still applies because I still had to write this character act out these horrendous and vile things. Much like @Stargazer31's character, this is what I had the character do:
- made a girl fall in love with him bc he thought she was unusual; took it as a little project/experiment
- made her do things she normally wouldn't do; was an enabler
- told her he loved her and wanted to marry her, even though he didn't
- gaslit her into questioning her own sanity at times
- manipulated and used people until they no longer served a purpose, usually ended up murdering them
- was the one who was behind some killings, which he revealed to the girl in the end, making her realise what she had seen was real
- the worst part: he took her against her will, even though she begged him to stop and that she loved him
Really gross guy, I tell you. The facade that he shows to her is really charming and kind though, so as I'm writing this Jekyll-Hyde duality of him, I could also see how anyone could fall for him.
Edit: I will add this bit: I am all for a more fleshed out bad guy. There are reasons why a character is so despicable (which is clear with Joffrey's case in GoT, his mother being Cersei). This gives the reader more insight and depth to their psyche, maybe some sympathy, but their actions are not always forgivable. It's kind of like seeing how much torture can one person endure before they break; which path will they take in life? A good one, where they show great compassion and kindness to others because they've felt great pain themselves, or a bad one, where they hope to bring as much suffering as they've endured, continuing the cycle? After all, humans make the greatest monsters.
I write quite a few hateable characters. The reoccurring one is a newspaper editor and chief. in his introduction he was blatantly sexist and had to write a retraction. He is a floundering troll. He is snide and condescending and feels his way is the only right way. He didn't do anything bad really, he just says things that are disagreeable, but very common for the time frame of the story. I made him as a reoccurring voice of the times and to deliver tidbits of information on the ongoing mystery. He does get hate comments so I think I did a good job at making him detestable.
I 100% wrote Urien in Errant to be as loathsome as possible. Some villains are meant to be feared and kind of respected, but Urien I wanted to really make somebody who you just want to punch his smug face. I'd say going from the comments, I was fairly successful. People either really hate Urien, OR they hate that they kind of admire how charismatic and shamelessly confident he is despite being such an awful person. 
Like Dolores Umbridge, Urien is small, everyday banal evil given power. So Umbridge, she evokes the bullying teacher or nurse, who hides her nastiness in soft femininity and concern trolling. Urien I wanted to go more for "crappy narcissistic startup boss", He's all confidence and charming smiles that win people over and they all buy into him and want to follow him, but underneath it all, he's not as smart or as together as he seems, and he can get really nasty as soon as anyone criticises him or even just makes him feel like he's not top dog. Having spent time working for a number of London startups, I've met and even worked for or with a lot of people like this, so my premise was simple "what if somebody like that was given a really powerful magic sword and became king?"
Urien acts like an abusive boyfriend or older brother. He belittles people, gaslights them and worse, he gets away with it because he always sounds so confident that people tend to believe him. I deliberately set up Sarin to be a sympathetic character so that the audience would feel really angry at his terrible treatment of her. The fact that he then gets away with it is such a gut punch- it feels so unfair. I think the main thing that makes Urien work is how petty and rubbish he is, and how unjust it is that because he appears so shiny on the surface, nobody seems to see what the people he abuses or the audience sees, and so he just seems to get away with things. I want the audience to want to see some justice for the people he's hurt. I think most of us can relate to getting antagonised by somebody who never seems to suffer any consequences.
It'd be pretty easy for Urien to feel like a strawman, and it was something I worried about because... yeah, he's a white guy who siezes power and then the first thing he does is to try to kill off an asian girl because she criticised him, and then he tries to gaslight her. He even uses the word "uppity" when talking about her, which I thought would definitely clue people in that he's certainly inspired by a certain type of confident, educated, authoritative white dude who likes to think they're "rational" but as soon as they're threatened or they get a chance, they reveal a nasty mysogynist/racist/homophobic intolerant streak. The fact that he's a blonde upper-class twit who takes over a country called "Britannia" without a mandate and runs it into the ground I also thought "okay, surely somebody's going to see the Boris Johnson parallel here?" But... I think anyone who would be upset by it either hasn't noticed because they're reading the comic without looking for metaphors, isn't immersed enough in British culture to realise or wouldn't read the comic about ladies with swords with the sparkly rainbow ghosts on the cover? 
oooh, that reminded me a similar quote about the annoying character, by being annoying, annoyed the reader in real life, which feels more real than the fictional crimes the villain did.
that's an interesting tip, sometimes an awful everyday person can resonate reader's "hate senses" better.
In the end the power didn't change them, it only allowed them to reveal their selfish nature further.
Love that description 
......met some folks like that back in the day. Luckily never had to work with them for long.
That's a smart move. Sometimes what it takes to make a character despicable is for them to hurt a character the audience loves.
I have one character (so far) that is meant to be hated, now this depends on their motives for doing bad thing (not saying every bad thing is forgivable because it isn't), also show how that characters actions made your likeable characters feel, for example mine is total trash to main cast so i'm expecting everyone to hate him when their backstory is shown
. I haven't really made real villains just yet...
One character that instantly got reader's hate in my case was an old man, who continuously kept on complaining about the MC and it's subtly implied he used physical violence towards him. Also his design was supposed to point out how the character is a grumpy snob with little regard to others' feelings.
The other one I made that I don't think readers like much is a typical Mean Ex-Girfriend 
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