First-Then cards are one of the most simplistic visual cues for those with Autism. They are simple as well as effective.
This type of visual intervention presents to the student what need to be done FIRST, which is THEN followed by the reinforcement.
(I usually laminate each sheet so that I can write what the student needs to do first, and what the student will get after the task is completed, with a white board marker. For lower functioning students, I usually laminate each sheet as wel