Leveling side to side is normally done by driving up on some kind of platform so the wheels and tires take most of the weight. Some people use boards, some use plastic lego like blocks, some dig a hole on the high side, some just push a button, and some don't worry about it. If it is level enough to sleep in the it is probably level enough for all other purposes. :)
Regarding the hitch, I don't know many people who disconnect the hitch from the truck bed. Most just leave the hitch in the bed and carry it around.
To disconnect the trailer, You chock the tires on the trailer (both sides!), put down front jacks and raise trailer until pin is the correct height to pull out, pull lever on the hitch, make sure your trailer is at the right height and the tailgate is down (unless you have a V notch tailgate) and then pull the truck out from under the trailer.
After you pull the truck out, then is the time to level front to back using the front jack legs. When you get the trailer level front to back, then put down your corner stabilizers and finish hooking up everything. :)
The above is almost the exact same procedure as with a travel trailer with the exception of the hitch part. When done, you are ready to camp! :B
Barney