I have worked only small theaters. No partner. I own a clicker counter but find it inconvenient for theaters. It is better for something such as how many are coming in to a ball game. I count "29,30,31...." Then I count on my hands the number of people who go out (so I don't have to think about it). If the number is larger, then I have to think. At the end, I deduct the backward count from the forward count. It still isn't perfect. I recount by standing at the back of the theater after the movie has been going for a while and, when the movie creates more light, counting heads. If I know a family came in and there is a missing head on a chair, then a child is either in a parent's lap or has slid down. I think I had one count that required me not to count small children but others haven't mentioned it. I count payers, if I can tell. I knew someone who sat outside the theater screen door (a bigger theater) and counted who went in and out. Covert work can't be done that way, though. If the flow of traffic is unusual, it helps to count when they leave, but even then there are front exits and back exits. In that case, I stand so I can see the people going past me but also count the shadows going out the front door when it opens. They usually leave as the credits are up, so the lights aren't yet on. Again, some of this only works in small theaters. I have to say "Hi!" to people who speak to me while still counting in my head. It is not as hard as it seems in this description, and I don't always feel that I need to recount, because the theater isn't full. Sometimes people are already in the theater even though I arrived early, so I count them then and later, just to make sure. The point is that the count should be very close or exactly the number that the theater has. If it is drastically off, then the counter probably made a mistake, barring any groups of teenaged jumpers. I have caught teenagers letting others in the locked fire door and alerted staff. One time, the theater owner, upon seeing my letter of authorization, asked me to also keep an eye on the refreshments crew because somebody had been pocketing money. I didn't see any wrong-doing there. This isn't just a job; it is a responsibility. Do your best always. I wish these assignments paid better.