Yes I started packing and unpacked etc several times in our old place. I never did feel quite at home there!
What I did was start with things on shelves, ornaments, clutter. Sorting out as you go - unless you are pushed for time, in which case don't, as you will go mad - the hardest bit of packing is the decision making, so wait till you are there and do it - also stops you chucking out curtains that will fit a new window, etc etc.
Try to put things you won't need in boxes first. Things rarely used.
Label each box and stack in one place.
I got loads of flatpacked boxes from local pharmacy - they send them for recycling in big bundles and are happy to give you them usually instead.
Don't worry if things go in odd boxes, ie some ornaments with some old cassettes/videos, books etc. As long as they are same level of use, ie rarely, you'll be Ok to leave them unpacked for a while.
Obviously don't pack books all in one box, your removal men won't be able to lift the box. Pack kitchen stuff wrapped in aprons/teatowels etc, saves on newspaper...
that's all I can think of for now.