listen to lots and lots of music. vary the styles, listen to artists from 30 years ago or a song just released yesterday. the tunes will give you a great basis if you can relate them to the character you're trying to create.
welcome to fh! don't feel rly discouraged abt being "too old" for stuff, fh or otherwise, i'm 18 and i'm still the biggest babey for fh, aj and wizard101 so like. don't distance yaself from things ya like, just have your interests man! hope 2 see you around<3