To add what's been suggested already is make sure both front legs touch at exact same time to either the ground or blocks. Makes no difference if one side is lower than the other, just make sure they hit at same time. Before our 6pt, we did what you have to do and always carried different thickness of boards (ie: 1/4", 1/2" pieces of plywood say 6x8 or so, 1"x6"x12"s, 2"x6"x8") to place on the ground to spread the weight out some and to shim as needed so pads hit at same time.
Once level side to side 1st, like Old Biscuit said, wheel chocks on BEFORE unhooking and off LAST after you hook up ready to leave.
If not done already, add a side level w/ graduation marks to left side of RV and a big bubble level to pinbox as that one tell you how much your off and which side.
The landing legs will be trial and error----sorry. BUT if you have or add the side level, remember: bubble to rear of RV, front has to go up. Opposite is true if towards the front. Outter legs should extend approx 18"-20" for reference. The more landing leg(s) you have out. the more "wiggly" the RV will be.
After you get the side to side done, wheels chocked, unhooked and leveled front to back, then you can lower the rear stabilizers. Hint: use a cordless drill if they are the crank type.