How to fillet halibut

http://www.tillamookbayboathouse.com/halibut.htm

if you're not that comfortable with your knife skills, cut the halibut into sections no wider than your fillet knife starting at the head and working your way back. Then you can just cut down through the lateral line of each section and sweep easily across to the outer fins.  An 8" fillet knife using this method punches out a bunch of ~1# fillets (unless you actually caught a flounder ) Besides, are you actually gonna cook up a whole loin like that?

The roast method works great for halibut! Only thing I would add is when you are cutting through the back bone either cut between the bones or use a heavy knife and a mallet to get through the bone. Make sure you hit the knife with enough force to get through the back bone with one shot. If you don't get through in one shot you will bugger up the meat on the bottom half of the fish. A sharp strike is more important than total force.
Good Luck Guys!

I have always found halibut easier and cleaner to fillet than salmon.  Just follow the natural dotted line (lateral line) and the lay of the bones and its fairly simple.  I also do like Nothing suggested and break sides down into "knife manageable" sections/strips, especially when removing the skin.