Machine Obliques Exercise:

Read all the instructions on the machine, and perform the workout according to the instructions. General Instructions: Set the desired angle that you'll be allowed to move. The maximum is typically 90 degrees. Adjust the height of the seat. Sit down on the oblique ab machine.
Contract your abs to move the machine out to the furthest angle from the center of the machine that you previously set. Exhale when you reach the farthest degree of rotation, and inhale when returning back to no degree of rotation. First do one side of obliques for reps, then position the angle of rotation to do the other side of obliques. Squeeze your abs and pause when exhaling.