Whole BBQ Salmon
For the impressive dinner serving, you will want to BBQ a whole filet, bigger the better.
A lot of people BBQ salmon by wrapping it in foil, to avoid it sticking. However, using foil you don't get that BBQ flavour from the oils searing with the heat of the grill, giving that distinctive crisp outside texture.
For this, you don't have to do much preparation if you don't want to - fresh salmon is so tasty, your guests will marvel at your cooking ability even if you've done nothing. But if you want to flavour it easily, you can press some lemon pepper into the flesh or some fresh ground black pepper.
Trick #1 for BBQing salmon directly on the grill is to oil the fish or the grill, or better yet both. Brush olive oil onto both sides of the filet. Place on grill FLESH SIDE DOWN.
Trick #2 is that you can only flip the fish once, because if you try to flip it a 2nd time, it will stick and you'll have a nightmare on your hands. So you need to make a good estimate of cooking time and stick to your plan. You can bank on about 10 minutes total per inch of thickness. You first cook the flesh side down 5-10 minutes, then flip.
Trick #3: you need to flip the whole fish at once, or it will fall apart. This needs multiple spatulas and often a second set of hands means you don't lose meat into the grill!
You can cook it skin side down until ready, the two sides don't have to cook even amounts of time. Use a fork in a thicker part of the filet, it should flake easily and be orange-pink and juicy inside - not red and not dry. Don't overcook it! And also be aware that when you take it off the grill it will keep cooking for a few minutes under its own heat, so if just slightly undercooked, it will probably be perfect by the time you serve.