Take the thinnest cloth you can find e.g. a thin tea towel, a vest or thin t-shirt. Soak it in cold water and wring it out fairly well. Fold it into a strip a similar width to your neck and lie it on a hand towel that has also been folded to fit your neck but that is still slightly wider than the damp, cold cloth. Wrap the whole thing, with the damp side against the skin, around your neck and pin or hold in place with a scarf. Lie down somewhere warm and comfortable for half an hour and relax. Remove the compress and wear warm clothing around your neck for the rest of the evening. This should have the effect of minimising the damage to your muscles and ligaments and helping your body's repair mechanisms to kick in effectively.
More information on hydrotherapy
What else should you do?
Never immobilise your neck with a collar or layers of scarf unless you have been told to by an orthopaedic consultant. Immobilising your neck will interfere with your body's normal healing and protective mechanisms and will place more strain on weakened structures when you take it off!
Only take painkillers or anti-inflammatory drugs (like paracetamol, aspirin, ibuprofen, Nurofen, diclofenac, Volterol or codeine) at night or at the end of the day. Painkillers mask the normal symptoms of healing and may allow you to put excessive strain on already injured tissues, so do not take them before activity. However, I am not a sadist and if you have a banging headache and its your one week of the year on the slopes, then just take the minimum possible dose to get you moving.
Even if you feel fine the following evening, repeat the compress to enhance the ongoing healing.
Types of strains and sprains
How your body heals injuries