Another technique that I found handy when replacing a Macbook keyboard assembly: I used a piece of foam roughly the same size as the notebook, and stuck the screws in their representative places after they were removed.

That model in particular had many screws that shared the same pitch, but with different lengths. The thought of piercing something with a 10mm screw in a hole meant for a 6mm screw was scary. I thought this technique worked well.

I use an icecube tray. same idea though.

We use a simple sheet of pre-printed paper with diagrams for common laptop parts and areas, and then cover it with sticky-side-up packing tape. Each screw gets stuck head-down to the tape, according to the precise location and laptop part it came from.

This. Snapping digital photos is so easy these days, and you'll know that your "notes" are both true and have enough detail.

I use my Flip for this. Photos good, video better. Also a great idea for when working on cars. I'm thinking of getting a gopro sd hero so that I can track my attention as well. For only $100 why shouldn't I document all of my repairs?

A trick I sometimes use on cars is that when you take each part off you put all the bolts in a ziploc and mark it, then put the bags in series in a cardboard box or whatever...then you just take each bag out of the box in reverse during assembly since typically the same parts go back in the same way...helps avoid the extra screw (or the dreaded short one screw/nut/bolt which is usually more puzzling for me).

I always want to do photos but I am usually too dirty and/or lazy.

Egg carton!