Not stupid, un-experienced; once ya' done it, you'll know. Drain like you surmised; loosen all the bolts a turn or so, then the lower few some more and pull the bottom of the cover away from the housing to drain. Clean the gasket surfaces on the housing and cover, and generally clean everything up. Now, here is where everyone has their own way of doing things: me, I use a new gasket, flexible gasket sealer like Permatex, or your favorite brand, put a thin coat of sealer on the housing and cover, stick the gasket on the housing and install the cover. Before putting the cover on, make sure that the sealing surface is flat and even; sometimes the bolt holes get "dimpled" and should be flattened back out with a hammer and dolly of some sort - I use the end of a piece of flat bar for a dolly. I also use a couple of studs - 1-1/2 inch long bolts with the heads cut off will work nicely, too - to screw into the housing to hold everything in alignment while I start a few bolts. To re-fill, there is a plug with a square "socket" hole in it on the right front of the housing about where the pinion "snout" flares into the housing; remove it, and fill until the oil level is just below the edge of the hole; oil comes in plastic bottles with a spout and a small hose, or a jug with a pump and hose. Close it up and you're done - except for getting rid of the smell.

Lke I said, everyone has a different way of doing things like this; this is mine.