300 degrees @ 1 hour per lb (or until internal temp is around 170), make sure you cover with aluminum foil.
So if you have a 6 pound pork shoulder do it at 300 degrees for 6 hours.
If you're Puerto Rican most of them like the fat crispy so the last 30 minutes of cooking turn up the temp to about 400 and remove the foil.
Always roast with the fat side up. That's for pretty much every meat.