How to deal with arrogance

I would say you made the first step to identify there is a problem. Just keep in mind that you should always treat others as you would want others to treat you. Is a good rule of thumb. If you think.it would offend or upset you, then it will probably upset others. Confident is goos, arrogant people need an ass kickin.

Calibrating your behavior, walking lines isn't always easy. Though it does get easier with age and social experience. But you know what's even less easy? Explaining these fine lines and behavioral subtleties in words.

The only thing I can say is try to look at Confidence-Diffidence as a continuum, with gradations and notches in it. Too much diffidence and (some) people lose respect for you and/or try to take advantage of you; too much confidence - arrogance - and you'll put people off, and in your case, yourself included. So, whenever you feel like you're reaching a 7 or 8 towards the Confidence end of the spectrum, slow it down and maybe take it back a notch, especially when the situation doesn't call for it. So when you feel like you're bragging too much for example without any good reason, offset that by some humble line like, "Though I'm sure not the only one who can pull that off."

I say "when the situation doesn't call for it" because context also matters. If you're in a position of authority or leadership for example (teacher, boss, cop, bouncer, parent, or even husband for the more traditional-minded folks), it's not only accepted but expected from you to behave more confidently and dominantly than, say, when you're with your buddies having a beer, in order to keep some order and function in whatever you're running. Same for when you're in some heated or confrontational situation, or when you're clearly getting assaulted in some way. In all of these, you have some more social leeway on the Confidence continuum.

Typically, having a good feel of social cues and repercussions will naturally prompt you to scale your assertiveness back and forth so as to preserve your standing, popularity, social connections, status, etc. and be neither shunned nor walked over. That's what "social skills" are about.

Just don't put other people down and act like you know better without any substantial proof of your knowledge, and you should be golden.