Yeah, it's not like.... American school clothing guidelines harsh. You can generally have a character in a bikini or a low-cut top or dress without issues.
If you're not showing genitalia or nipples, you generally should be okay. That said, IF showing nipples, even male ones can sometimes be deemed inappropriate if it's in a sexy context.
With violence, avoid excessive flowing, running or spraying blood, brutal viscera, internal organs and gore etc. A bit of blood is okay. Basically, about as bloody as you'd see in a Shounen Jump manga like Naruto, one Piece or My Hero Academia should be ok.
With swearing, a bit like a PG13 movie. "Damn" and "Bastard" are okay, you can get away with the odd "sh**" or "Bit**", but avoid things like "fu**" and especially "*cu**" or "motherf-er" unless you're gonna give it a mature rating. If there are any slurs, like racial or homophobic ones, the chapter should be marked mature AND have a content warning.