Streches that i could do do get me more flexible

Im in ballet and I can do the splits but some days I cant, I want to know of some streches that I could do do get me more flexible, and how do you strengthen yourself for the bridge?

Back - be extremely careful!
* Lay down on the floor.
* Sit up straight, leaving your legs out in front of you. They don't have to be flat.
* Turn your upper body slowly, and make absolutely sure that you stop turning when it starts to hurt. It is relatively easy to damage your spinal cord if you stretch improperly, so pay attention.
* When you stop turning, hold that position for five to ten seconds. Turn the other direction, and repeat.
* Try and do a backbend/bridge but be careful not to go too far! Once you are in the bridge, push through your shoulders and try to put your legs together and straighten them. Don't go on your toes!
* You can also stand up with your arms hanging out to the side and then very slowly twist from side to side.
* Another stretch is to lay flat on your tummy and then use your arms to put yourself in a snake or seal stretch!

Legs:
* Sit down as you did before for the back exercises, only this time, make your legs as flat on the ground as possible, right beside each other.
* Stretch down towards your knees. Do not bend your head to face your knees, face forward.
* This will also stretch your neck muscles; if it hurts your neck to do this exercise, face your knees and stretch.
* You can also sit down with your legs straight out and take your right leg and swing it over your left leg a few times. Do the same with your right leg.

-wikihow