In my (biased) opinion, ballet and dance in general is a sport where all parts of your body need to be healthy and fit, since they need to have strength all through their bodies, as well as balance, agility, and stamina.
As a dancer, I've been in a lot of ballet classes and have experienced a lot of ways to stretch. If I make the account, I'll probably make more tips like this with different exercises, but for this tip I'll be focusing on barre stretching, which will make you more flexible and limber.
-A chair, table, bed, basically any flat surface about waist to stomach height. The higher the surface the more you'll be stretching.
How to stretch:
Stand facing the surface, which will act as your barre. Life your right foot up and rest it on your barre, straightened in front of you. If you feel your hip rising, try to push it back down into its place.
Lean forward into your leg, pointing your toes and trying to get your forehead to your knee, but stop when it gets uncomfortable.
Hold this for about 20-30 seconds, then bend and straighten your supporting leg at the knee 3 times, staying bent on the 4th time. This is called a plie. Hold your plie for another 10-15 seconds, the stand up straight.
Next, rotate your hip, leg, and body so your leg is to the side of you. MAKE SURE YOUR HIP STAYS DOWN AND DOESN'T RISE UP. Do the exact thing you did for the front, except afterwards lean away from the barre for 5-10 seconds.
Then, rotate once again so that you're facing away from the barre and your leg is behind you. Bend your torso forward towards your supporting leg, once again trying to make contact between your forehead and knee, and repeat the steps for the front.
After you've held the stretches for the back, try to lift your upper body up to standing without using your hands or taking your leg off the barre. Trust me, it's more difficult than it sounds.
Finally, repeat everything listed above, switching to having your left leg on the barre.
This was some basic ballet barre stretching, hopefully you'll like it. :) If you're trying to get your splits, doing this every day should help with the right and left sides. If you have any extra questions, just PM me or ask me in the comments!