Where is the toilet?

I leave for Tanzania in a week, and at the moment, I’m envisioning some “what ifs” that take on bizarre dimensions the more I imagine. What if I arrive at the Kilimanjaro Airport and need to use the restroom before I find my Tanzanian host? Although many people in Tanzania speak English, not everyone does. My Swahili dictionary says “toilet” is choo. I suppose I could tap someone on the arm, and say “choo choo.” Even better, I could say “choo choo” while I cross my legs and wince. Somehow this lacks dignity.
Even if I manage to get across my question with or without my dignity in tact, will I be able to understand the answer? In Teach Yourself Swahili, the taxi driver (teksi dereva) in chapter two conveniently gives three directions: left, right, and straight ahead. But what if the choo is around the corner, through the alley by the Kwik Shop after two traffic lights, and don’t mind the chickens in the road? How do I communicate to someone that they have only three choices for an answer? Multiple choice works on paper, but in an airport when I have to go to the bathroom? So on the airplane, I’ll write kulia, kushoto, and moja kwa moja and then I can point to each term, raise my eyebrows after I point, and move on to the next term.
That should do it.
Now I’ll have to figure out how to get back to the airport, having passed the two traffic lights, the Kwik Shop, and the chickens in the road.