They are more active at night so thats the best time to search for him. also look at places that is warmer than the rest of the house. like under the fridge, any warm spots. it you have hard floors you can put down flour by the walls to see it he crawl thru it and left tracks. everything is new to him right now and that usually makes them more active so make it dark where you think he might be, be quiet use a flashlight and look for him.