Well, I think the first thing you would want to teach is the actual touching of the cup, or whatever final behaviour you choose. I would teach him to target the cup, then put a treat under it and ask for the target. Once he understands that properly, add in a second cup far enough away he's not distracted by it, then move it closer by increments. Once he's got the two cups then add in a third. At this point he should understand what you want him to touch. Then start making it more difficult.
At least that's how I would teach it
