If a perm has damaged your hair, you may be able to repair it by using silicone products that make it appear softer and a little more manageable. Additionally, you can use a hot oil treatment on your hair, as the perm will have stripped your hair a lot and dried it out to an extent. As much as possible, you want to keep your hair moisturized. If the damage is too bad, you might need to cut your hair and grow it out to be healthy again.