M.N.
We gave suckers or little treats at first. Even fruit snacks or special crackers work. After she was getting the hand of it,I didn't want to use food or anything big for every time. I made a potty chart. I put rows on it and when she went pee, we put a little sticker on. When she went poo, we put a big sticker on. When the row was filled, she got a "prize". I just went to the dollar store and got her stuff; jewelry, bubbles, chalk. She knew there was more than one necklace or whatever in there, so I just told her she had to fill up another row to get it. She trained fairly easy, except poop at first. She held it for like 3 days because she didn't want to go in the potty. she asked me for a diaper so she could poo and I told her no, I finally put her on the potty and made her sit until she went. For that she got a bigger reward. I think we took her to the store and pick something (within reason) Next poo was held for 2 days, after that, we never had an accident.
Good luck.