Grilling fish is tricky without a grill basket, but don't let that deter you:
* Spray the fish with nonstick cooking spray or brush it very lightly with oil.
* Place the fish around the edges of the grill, away from the hottest part of the fire (Don't try to lift up the fish right away; it will be stuck to the grill).
* Start checking for color and doneness after a few minutes, once the fish starts to release some of its juices.
* Flip it over when it's got light grill marks.
Fish on the grill needs to be attended very closely and only takes a few minutes per side. If the filets are an even thickness, fish can be cooked through by grilling it on one side only.