Kill the heat at the end of the boil and wait for all boiling activity to stop. Add 2-4 ounces per gallon (15-30 g/L) of your hops, and whirlpool with the kettle covered for at least 60 minutes prior to chilling. You can add an additional 1-2 oz/gallon of dry hops if you wish, but I don't usually bother. No boil additions are necessary. You will get plenty of bitterness from the whirlpool, but it won't be a harsh bitterness.
I've tried dozens of different hop schedules for my IPA's, but this one is the one I keep coming back to. This gives a massive hop flavor, and enough bitterness to balance it without becoming abrasive.
You will probably see a bunch of other suggestions from other brewers, and they will all be good. Try a few out and decide what you like the best. It is worthy (and tasty) research.