Let it cool down to room temp then put it in the fridge. How are you cooking the chicken?
If you want it for sandwhiches then chop it into large bite sized pieces and place under the grill for 3/4 minutes. Or, if you want it with mash, roast, etc then bring it up to temperature in a pan of gravy/stock, add a bit more water than normal so that it's the right consitancy when it's ready.