We picked out a special toy for our daughter, that she was allowed to have the first time she pooped on the potty. I keep a box of small things I find that are on sale, or from the dollar store - coloring books, puzzles, finger puppets, books from the used book store, that sort of thing - for bad weather, or traveling, or whatever. The second time, she was allowed to "shop" in that box. After that, she got a sticker chart - five stickers got her another chance to pick from the box. After two prizes, she stopped reminding us to count stickers. After a while, she stopped asking for stickers, and we put the chart away. I NEVER reminded her that it was time for a prize or sticker. If she forgot, all the better for me!
Also, if your daughter is using the "big potty" instead of a potty chair, put a stool in front of it. BM is more comfortable for the little ones if they have somewhere to brace their feet.