Home inspectors are often asked to pair outlets to breakers or electrical circuits. Sometimes these job are easy but can be challenging at times. You may be able to do a great job using a volt probe and turning the power on and off, but this would take a lot of time and patience. Thus, we highly recommend use of some breaker finders from reputable manufacturers.
Here is a short list of them: Amprobe, Extech, Ideal Industries, General Tools.
Breaker finders are relatively easy to use. They come with a transmitter that you plug it into an outlet, and a receiver, which you use to scan breakers in the panel box. Finding breakers is that easy most of the time unless some of circuits are disconnected from the panel.
Please remember to test if wires are live or not as a security measure. Also make sure the breaker tracer works with de-powered circuits. Some tracers require current for proper tracing.