Is there an easy way to label breaker box without flipping switches?

https://www.thespruce.com/creating-a-circuit-directory-1152309

Grab a partner and just do the flipping thing and label all the breakers. A bit of a pain but you will be grateful later when you have any electrical problems or work done. This advice is from an electricians wife.

Only if you know exactly what the switch controls.

Wrote on mine with a Sharpie, beside each breaker on the gray painted metal. You determine what to write based on exactly what you are doing, turning the breakers off and seeing what goes dead.

Not sure I understand why this isn't obvious. If you are asking is there a standard code that you write, no there isn't. If you flip a breaker and the outlets at your kitchen counter go black, you simply write "kitchen outlets" or anything else that makes sense to you. It multiplies as a house gets older that there will be odd electrical branches that you wonder why they are connected. All of the ceiling fans in my house are on the same circuit as the light over the kitchen sink. Go figure.

You will still need to check each time to make sure that the power is off where you are working.

That's the only way I know!

do get a partner to help. it goes much quicker

If you are by yourself you need a plug-in radio. Just keep throwing switches until you hear the radio go silent. That is the shortcut, or at least the only one I know. It is good to have friendly neighbors.