One of the reasons why many people want to jump back into class is that they're worried that their teacher thinks they're being slack by taking time out. However I've talked to a lot of teachers about this and the majority of them would much rather that you take some time out and assess what's going on rather than dancing through an injury.
3. Assess the damage
Next, you want to actually see what's going on and to determine the next step. If it's an ankle injury you might want to start by gently pointing and flexing the foot and sickling it in and out to see where it hurts and how much it hurts. The important thing here is to do this testing yourself, using your own muscles rather than having someone else do it for you. What you're trying to find out what structures are actually damaged and how badly.
If there is a fracture or a bony issue it will often be quite a deep sharp pain. If you feel this at all you must stop immediately and move onto immobilising and icing the area to prevent any more damage. If it's a ligament it will often be sore if you move it in a certain direction and it will also be sore when someone else guides it into the same position. If it's a muscle on the other hand then it will be sore when you do the movement but it won't be as sore if someone else guides it into that direction. Either way you want to work out how much pain there is. If there's a lot of pain you should immobilise it, however if its just a slight pain when you start doing these movements then you may try placing weight through the foot to see if there is an increase of pain with that.
R.I.C.E stands for rest, ice, compression and elevation. This is important in the initial stages to help reduce the swelling however do remember that swelling is natural process that is designed to flood the injured area with lots of white blood cells and fluid to heal the injury. The fluid and swelling is designed to immobilise the joint so that you don't re-injure it. You don't actually want to remove the swelling completely but if you have too much stagnant swelling this can interfere with your healing and treatment later on.
Rest - This is obvious, don't continue to walk around or dance on it if it's quite sore. You want to take time out from class.
Ice - It's very important that you apply ice correctly. A lot of people take one ice pack, pop it on and leave it there for a couple of hours and then forget about it after that. This is not what you need to do! Ideally get a fluid ice pack (e.g some ice cubes in a bag of water) that will mould around the joint rather than using a hard ice pack on one part of the area. You want to apply the ice between 10-20 min depending on the size of the area and the severity of the injury. Then you want to remove it for 20 mins before putting it back on. You want to have the ice on and off the area for the next 24-48 hours depending on the severity of the injury. This will allow new blood flow to keep coming into the area whilst preventing too much fluid from staying in the area.
Compression - You can apply some compression with a gentle bandage but make sure not to wind it up too tight. Keep an eye on your toes to make sure that they don't turn white or blue!
Elevation - It's not enough to pop your foot up on a bag. Your foot should be above your knee, which is above your hip to allow the fluid to come back down into your lymphatic system and reduce swelling.