请留步。

Say it as you begin to walk away. Usually, you say it when you reach the first 'exit' point. This could be the office door or the living room edge. You can pair it with a small wave or a slight bow. It is often repeated once or twice if the host insists. It sounds smooth and very sophisticated.

Use it in almost any setting where someone is hosting you. It works at a business meeting after the final handshake. It is perfect when leaving a friend's apartment. Use it at a restaurant if someone is walking you to your car. It makes you sound like you really understand Chinese etiquette. Even if your Chinese is basic, this phrase earns huge respect.

Do not use this if you are the host. That would be like telling your guest to stop moving! Also, do not use it in very casual, 'bro-like' settings. With your best friend, a simple 'Bye' or 走了 is better. Using it with a younger sibling might feel a bit too dramatic. Avoid it if you actually need help finding the exit.

Chinese culture places high value on the 'host-guest' dynamic. A good host must walk a guest as far as possible. In the past, this meant walking to the city gates! 请留步 was the polite way for the guest to 'release' the host. It balances the host's duty to be hospitable with the guest's humility. It is a beautiful dance of mutual respect.

If you want to be even more polite, say 请回吧. This literally means 'please return.' For a more casual version, you can say 不用送了. This simply means 'no need to see me out.' In very formal letters, you might see 留步 used alone. But for speaking, 请留步 is the 'Goldilocks' version—just right.