Hi L.,
Your idea regarding the color coding stickers is a good one. You've received some great tips but here are a few more.
In addition to change have a calculator and extra stickers handy, wear pants with lots of pockets (like cargo) so you can keep big bills in one and smaller bills with change in another, but keep all the $$$ on your person.
Make sure your husband or someone else is home so you are not doing it alone, weird things happen. I also always have my cell on me.
I would definitely also advertise online with Craigslist, the day before or first thing in the morning the day of.
Tie a a couple of balloons to your mailbox along with signs on the street to help people find your house.
Start keeping all your grocery bags and any cardboard boxes to put the purchases in.
I also tried to give lots of incentives for buying more. (Buy 10 paperback novels and get 2 free!).
There are lots of great websites with good tips too, just google tag garage sale tips advice.
Good luck and have fun!!!
Liz
P.S. Have your kids pick out which of theittoys/vidoes/books etc they want to sell, let them set the pricing and tell them they get to keep the $$$ from whatever they sell.
A great practical lesson in finance and limits the tears if you accidently sell the huge stuffed purple Barney that has been sitting in the back of their closet for 3 years but apparently now that it's gone they can't live without!