If I want to make sure I paint something before I attach to another part ( like say attaching landing gear wheel wells to wings on an airplane) I circle that part of the directions and write something to remind myself to paint it. Like I might write "Paint this part first" so I know to do that. Or like if I was gonna assemble a car dash, if it's possible I paint it and detail it before I attach it to the interior of the car, but I make sure I circle it on the instructions.

It also helps to write down a kind of build outline. Like what majore parts you can assemble that you can paint together with no problem and do those first and then look at what needs closer attention. Same with decals.

There isn't really a wrong way to build a kit, just figuring out what works for you is the hard part.

Hope this helps you in some way. Take care