How to become more flexible?

i have recently started to work on myself because im in gymnastics and i need to get flexible its been two days since i started and now i can hold my leg up pretty far up anyways what i did to acheive the was i like layed on the flo0or then i took a belt and put it around my ankle and i pulled towards my head as close as i culd without it hurting really bad anyways so i did that 5 times to each leg for about 10 seconds each and also i kick my legs up about 10 times in a row trying to get it higher and i just basically do the kicking thing every 30 minutes well like just instead of doing it 10 times i just do a couple while im walking towrds the kitchen or soomething and i also sit on the floor with my legs strecthed out together and flex my foot and try and touch my ankle then toe then the floor then try and lay down and pretty much do those exercises and youll get to where you can do the splits=]