I'm a really big fan of Twitter, my handle is DMBrigman
As others have said only posting your comic updates doesn't really get followers. Think about it this way with people you socialize with in real life, you don't always want to hear only about buying their book/diet supplements/jewelry/etc. So, you have to give people a reason to follow you. That means retweeting interesting content, participating in discussions, answering people's questions, posting original content like sketches and WIPs.
I suggest follow people, think about what about their feed that you like and don't like, then let that guide your own feed. Post about things you are passionate about, there are communities for D&D, wrestling, and TV shows. If you can connect with someone over a shared hobby and make friends then they may check out your stuff. Ultimately, make connections with people, make friends, if people like you then they will check out your stuff because you made it. Social media is as much about selling yourself as it is selling your product.
Just be mindful of the purpose of your account, if it is your "professional" account then you should try to act like you would at work, otherwise you risk turning off potential readers or employers.