I had to have a good system as my stuff was going into storage for a bit!
I raided the children's colour paper stash, chose a colour for each room, and then tore the paper into squares (saved me cutting with scissors) So lounge was yellow, dining room was green, our bedroom was red etc etc.
I had a hard backed A5 book and taped a strip of the coloured paper onto a page with a bit sticking out of the top to book mark that room in my book.
We had normal packing boxes, I wrote in black marker on 5 of the squares per box, ie when I first started I did the kitchen for items that I wouldn't use before we went. So on 5 squares of green paper I wrote "1" and wrote down absolutely everything that went in it or stuff like "drawer contents of sideboard" etc.
The squares were taped with clear parcel tape to each side of the box and one on top. That way when they are stacked you can still see what box is what.
It meant when we moved, the removal men could easily see what boxes went in which rooms. The children chose their own colour for their stuff.
For furniture that we collapsed, we used masking tape and wrote on that, I also put all the fixings from the furniture into plastic zip lock bags, labelled them, and taped those to the furniture pieces.
The coloured label things removed quite easily as I passed the boxes on.