Please not that I am not medically trained. This is from my experiences of several twisted ankles.
Step 1. Can you stand on it? If not then you need to call for help. You do of course have a phone with you, if not then find a stick for support and some friendly dog walkers to help you get home. (I have done this.)
Step 2. If you can stand on it, can you walk to help without too much pain? If so can you run without it hurting? If you can run without pain, then it really isn’t too bad. Don’t run if it is painful as it will only make things worse.
Step 3. You make it home and have a look at the damage. If it is swollen and sore then keep it elevated as much as possible and use an icepack.
Step 4. When you can stand on the leg again then you need to work on balance. Progress as things improve from single leg balance to going up on your toes and mini single leg squats. Do not consider running until you can hop on that leg without pain and keep checking if anything you do makes the ankle swell more. If so reduce what you are doing.
Step 5. When you can hop and feel ready to try running again, wear some ankle support and stick to smooth surfaces to begin with.
Step 6. Keep working on balance and ankle mobility as you progress the running. Check that both ankles move the same.
Going over on your ankle can range from not much damage at all, to bruising from below the knee right down to toes or even a fracture. The most extreme cases will require 4-6 weeks off running. As with all injuries, avoidance is best, so look where you are going and work on improving your balance.