Every young ballet dancer wants to dance in pointe shoes. And every ballet exercise, done properly, will prepare you to dance ballet in pointe shoes. Yet, there are special exercises you can add to your home practice that will prepare your foot muscles to do pointe work. There is a special gentle way (or two) that you can get more flexible in the ankle joint, if you need that.
First, a simple exercise that you can do - toe swapping. With feet flat on the floor, lift your big toe up and don't allow the other toes to follow, or even work at all. Sometimes in the beginning, your toes all want to work at once, and it feels very strange to separate the big toe from the others. Hold the big toe up for 10-20 counts.
Then, put the big toe down, and lift the other four toes of each foot. Hold them up for 10-20 counts. You will feel muscles working that maybe you have never been aware of before.
Secondly - playing the piano with the toes. Just like it sounds. Lift the toes, then place them down, one by one, starting with the big toe. Lift them up one by one, starting with the little toe. This takes practice to do properly. The wonderful thing with these exercises is that you can do them while studying, watching tv, or reading.
For more flexibility in the ankle joint, first it is important to relax the muscles at the front of the calf, all the way down to the ankle. This can be done with a tennis ball, or a "pinkie" sports ball. Kneel down and sit back on your feet. Work the ball down the tibial (front of lower leg) muscles, pressing into tender spots that are holding tension.
Once you are down to the ankle area, there are two ways you can stretch the top of the ankle/foot area gently. You can place the tennis ball under the top of the foot, above your toe joints (or you will stretch the toe joints, not the arch area). Gently press down on the ball, just enough to feel a good stretchy feeling from above the ankle joint into the top of the foot. No force is needed. This gentle stretch is simply to elongate and release tension in the muscles, giving you a little more point. Progress is gradual. Do not ever push into the stretch where you feel pain.
The other way to get a gentle (did I say GENTLE yet?) stretch is to lift the knee off the floor and hold it up. You'll feel the same elongating but not forceful stretch over the top of the ankle/foot area. You can hold these stretches for 15- 30 seconds and slowly release.
That's just a start. Get your own copy of The Perfect Pointe Book, for exercises to prepare for pointe shoes.