Okay goes size matter for a ring?

okay does size really matter to a girl like seriously what do women out there mostly like? is it good to surprise a girl with a ring what if she is a size nine and you want to find her the perfect ring that she would like im asking for alittle help her guys im clueless on what to do i actally thought about having some of my chick friends to go help me on this one i just want it to be the best thing she likes and surprise her were not togther anymore and i broke her heart terribly now im willing to do whatever and anything it takes to get her back because im madly still in love with her she completes my life and me as a whole.can anyone give me any ideas how do you get a girl back would surprise flowers be a good idea i even though about renting a limo and surprising her and taking her out to diner but i don't know if she would even want to get in the car???? help peeps!!!