The reason you get so many answers is because everyone has their own method.
We carry a 2x10 and a 1x8 both four feet long. We pull both tires onto which ever one is needed to level the low side. Then we chock the tires. Next we unhitch and level front to back with the tongue Jack.
The stabilizer jacks are lowered to keep the trailer from rocking, you may get a little lift as you relieve some of the spring tension but not much. You are not going to "Jack up" a corner.
The end goal is a reasonably level and stabilized trailer so the frig is happy and it does not rock from side to side.
This may sound like an arduous task but once unhitched and chocked, I usually have it leveled and stabilized by the time the DW has the water and electric connected and the slide out.
You may also discover the floor, frig, sink, frame and stove all have different opinions as to what "level" is.
Good luck and enjoy.
