These tips are true whether you are doing a u-haul style self move or hiring the pros.
1. keep a log. This is a must. Every box gets numbered, and then the contents and desired destination goes next to the corresponding number in the log. If you move with the pros, it will make their inventory smooth sailing and they will love you for it. Either way, you will be amazed when you can easily find that thing you just *have* to have right now!
2. If you can, assign each room, or at the very least, major areas its own color. Tag the box with its room color, and on move in day you can label the rooms so movers, (pro or amateur) can take boxes to the right space. It is so nice to have things in the right room when you unpack!
3. pack things from the same room together. This is the only way #2 will do you any good. Within the same room, you can mix things, say, heavy pots and pans with your dish towels to fill space without making the box too heavy to pick up.
4. Invest in your packing materials and then save them. Good boxes, if treated properly, will last you many many moves, and will save your stuff. Newsprint and bubble wrap are also essentials. Don't skimp, your stuff costs more than the paper! Dish packs are amazing for getting fragile dishes through a move, and they break down flat to be used over and over. Bubble wrap keeps a nice long time, but avoid keeping the newsprint if you'll be in one place more than a year or two. ( Mice could imagine nothing better than an endless supply of newsprint for nesting...EWWW)
5. If you have time, use moving as an opportunity to weed out your stuff and re-organize. sure, it would be easier to just throw stuff in the box, but who wants to unpack a hot mess in their new home?
6. *must have* box: a set of sheets for the beds you need, a towel for each person, a shower curtain and toilet paper should go in your vehicle and be clearly marked.
7. Finally, If you are using professionals, have your stuff packed when they arrive, have disposable cups for the crew to at least be able to have water, and be certain to leave toilet paper in the bathroom so that it remains "in service" throughout the day.