6) After The Sale
Remove ALL the signs you put out. You can use them for your next sale and you should not litter by leaving them out after the sale.
Resist the urge to re-stash the items that did not sell back in your house to try to sell again next year. Unless it is an item where you can drop the price in half, what did not see this year will not sell next year.
Donate left over items to charity. Take pictures of the donated items. If you donate your items you can use it as an itemized deduction on your taxes. Use https://itsdeductibleonline.intuit.com/ to create a detailed list and total for your donated items. Check with the charity to see which items they will take. Some do not take TVs, Computers, furniture, beds, etc. Highland Park has an annual neighborhood cleanup where you can drop off a number of items for a price https://www.highlanddistrictcouncil.org/ . See the file on this page "Donations St Paul - Minneapolis" for details on organizations and what they take.
Some items like computers or electronics can be recycled for free at places like Office Max or Best Buy. Policies on what they take or cost to recycle change frequently, check their web site or call the store.
Some items can be put on the curb with a FREE sign. If they are still there after several days you will have to find another way to dispose of the items.
Craigslist can be used to list larger FREE items that you do not want to sell. Include good photos in your post. Some charities will pick up items like furniture if you have 2-3 items.
Take down the remaining tables and return your garage back to a garage. Return any tables you borrowed.
Add up all the money in the cash box and subtract the change you started with. This is the total profit for the sale. Add up the totals by family member or neighbors if you had multiple people selling at the sale. Split the money.
Relax! You deserve it!
Start planning for next year.