How to find out where your boat is leaking?

I have a 16 ft smoker craft that is taking on water. It has a double hull and good working bilge pump. The leak is not easily visible and not sure how to find it. Any ideas? Thanks

Questions to ask yourself. Is it leaking all the time? Does it seem to get more water when running livewell pump? I would first check where livewell pump goes thru hull, then check fitting on livewell pump and hose. If nothing there, put plug in and fill with water up over your drain plug with it sitting level. Let it sit then do a real good exam all over the hull. Check motor to transom bolts especially the 2 lower bolts.

While trailered and level, put water inside the boat, and then see where it drips out.

Does your livewell hoses have water in them when your in the water? If so it may be that one of thoses is leaking.