Most people who hire a cleaner for the first time have the same two worries: whether they need to clean before the cleaner comes, and whether they need to be home. The answers are no and it's up to you.
Before the visit, the only helpful thing you can do is pick up. Clothes off the floor, dishes in the sink or dishwasher, papers in a pile. A cleaning crew cleans surfaces; it can't clean a surface it can't reach. You don't need to wipe anything down, and you definitely don't need to apologize for the state of the bathroom. We've seen it, and it's why you called.
On the day, the crew arrives in the agreed window and starts with a quick walk through the home so you can point out anything specific: a stone counter that needs a particular product, a room to skip, a pet that stays in the bedroom. Then they work from a fixed checklist, top to bottom in each room, dusting first and floors last.
You can stay or go. Plenty of clients hand over a key or a building code and come home to a finished apartment. Others work from home while the crew moves room to room. Either is fine. If you're there at the end, we'll walk it with you; if you're not, we'll leave it ready for you to look over.
The first visit is also where the 15% first-service discount applies. If it's been a while since the home was cleaned thoroughly, we'll suggest a deep clean for that first visit and a regular schedule after. Either way, you'll know the price before we arrive, and there won't be any add-ons on the invoice.