Divide everyone's clothes across the bags, so that if one goes astray, no one's left with nothing to wear.
Always travel light. You can almost always do laundry or get it done while you're away, so you really don't need to take enough stuff to wear something new each day. It also means that you won't have one or two weeks' worth of dirty clothes once you get home. You also need space for your holiday purchases.
Pack underwear in pillowcases to keep them together and make unpacking easier. Then use the pillowcases as laundry bags while you're away. Pile any dirty clothes into them when you pack to go home, so that you can instantly dump them in the dirty washing box on your return.
Put some empty plastic bags in your suitcase. They take up no space but are invaluable if you need to return home with wet swimsuits or dirty shoes.
Tie a colourful ribbon onto your bag handles so that you can instantly recognise your bag on the luggage carousel, and make it less likely that someone else might mistake yours for theirs.
Tip taken from Simply Wonderwoman: A Survival Guide For Women With Too Much To Do (Kyle Books) by Joanna Gosling, Dh103, www.amazon.com