Here is a more complicated situation: the box on the left will contain two switches, one for the porch light and one for the exterior string lights. Power comes in on one cable, one cable goes to the porch light, one to the string light receptacle, and then a fourth cable takes power to the next box on the circuit. I’ve labeled all of these but won’t be able to see them once the wires are stripped and the walls are up (I did make some notations right on the ends of the sheathing where the cables enter the box so if necessary I can pull the cables into the box to figure out which is which). To make it easy, I used tape and labeled the hot wires. Since neutral wires bypass switches, I didn’t have to label them, nor the grounds.