If you've got a nice bit of fat (which you should) score it with a knife but not deep enough to go into the flesh.
Pour some oil in your hand and rub over the skin/fat.
Rub salt into all the cuts in the skin all over.
Whack oven up to 240C or so. When up to temp, shove it in there for 25 mins. The skin will crackle
Then drop the temp down to whatever cooking temperature you want - the lower, the longer you have to cook it for, but the more tender it'll become. Just use a skewer to test the middle of the pork for the juices (should be clear).
I guess you could be clever and use a water and cook on a rack, but if you've got a decent amount of fat that should keep the meat moist, and you shouldn't really have to baste - but I guess that's down to the oven, and you have to make a judgement call.