Jeeze louise, this is very vague.
It’s so hard to give people general advice like this because it completely depends on your personal style preferences.
I would say the easiest place to start would be to go and scope out regional Op Shops (All the great finds and good bargains are hiding in the outer suburbs or country towns, Inner city Op Shops suck!) as well as reading up on all the best second hand markets in your area and doing one every weekend for a few months. This way you won’t be spending much of your hard earned cash but you can get heaps of different items and experiment. I always find my favourite quirky statement pieces second hand. Plus, it is a super fun activity to do with friends.