First of all, know that almost all people sleep just fine in the sleep lab. Before and during medical school I worked as a PSG tech, so I know this is true from seeing hundreds of people sleep well.
You’ll be asked to arrive at the lab about 7pm. You will work with one staff called a PSG Tech throughout your stay. He or she will show you the bedroom, and hook the testing equipment to you. They will monitor you throughout the night and unhook the testng equipment in the morning. If you need to use the restroom in the night, no problem, simply call out to let the Tech know.
Most sleep labs have bedrooms that look like hotel rooms with a double or queen-sized bed. You are welcome to bring your most comfortable pillow, and a favorite book or movie to enjoy before bed.

Keep in mind the information gathered during the overnight sleep study is so valuable in diagnosing and treating sleep problems that it is well worth it.