I've done what Tyler speaks of and it's good.

Here's another idea:

make a paste of mayo and Dijon mustard (amount of mustard to taste, I use 2 parts mayo to 1 part mustard). Coat the fish with that and lay on a couple of sprigs of fresh dill. Wrap that in tin foil, folding the edges so it's sealed, and then wrap it again same way.

Toss it on the top rack of the BBQ on med-low heat. You'll smell it when it's done, ~ 20 minutes.