I moved 5 times in 6 years (went into rentals between house being sold and new one being available) so came up with the following:
Book a removal firm.
Start packing the loft and garage up well in advance. Most people underestimate how much they store in those two 'rooms'. Be brutal about what you want/need to keep - I hope your OH isn't one of those like mine who absolutely HAD to keep 20 ceiling roses, 35 plugs and 4 jam jars full of assorted screws 
.
When packing, make lists of the contents of the box and stick to the top with at least 4 pieces of sellotape! Use thick black marker pen to label box.
Use double walled cardboard cartons wherever possible - single walled ones are a pain. Get a tape dispenser and get decent brown parcel tape! Use plenty on the bottom of the boxes.
Assume boxes of fragile items will be dropped and wrap the contents in bubble wrap, not just tissue/paper.
Dont assume that the removal men/women will put the correct boxes in the correct room at your new house. Be prepared to stand on the doorstep directing pieces of furniture where you want them to go so you dont have to spend time and energy shifting them when others have gone.
Make sure you have clean bed sheets etc to hand so you can get kids beds done in the new place before anything else.
Finally, be prepared to make lots and lots of cups of strong tea (usually 2 sugars!) - the removal men/women will love you for it!
Good luck x