Leveling side to side method from seasoned campers

Simple but effective?? I built a ramp out of an 8 ft long 2x8. Cut into 2 4ft long pieces. One piece was cut diagonally to make two triangles. The second piece is screwed onto these triangles to make a 4 ft long ramp. (put small braces between those triangles). A large/visible level on the nose of the trailer let me know on which side to put the ramp. Then back onto the ramp until the level shows level. Block it up then level front to back and you are set to go!!