Newbie first time setup/usage list

Thanks for the good ideas, I have them on my list. Where is the best place to check if the camper is level? My truck camper, I used the floor of the freezer and then put stick on levels outside. I know side to side first, chock the tires, unhitch and then use the front landing gear to level front to back. Is that basically the order? Do I check level from the counter top? Freezer floor? Entry door frame? Rear bumper? King pin?