Taking care of mixed hair!

I am half African American and half Aboriginal.. blessed with long naturally wavy hair.. but I don't think I'm taking proper care of it! It's very dry and very frizzy and I don't know how to properly care for African hair as I was never taught! I either put mousse in it or straighten the crap out of it and I'd like to know if there's anything I can do to my hair and take away the frizz and just have my natural curls but smooth! If anyone could help me out I would really appreciate it :)