ya might want to try a weekend thats at the end or very first of the month-- when government aid checks go out. I hate to say it like that but those are usualyl money makers down here in the south. Those and right around holidays. like 2 weeks after thanksgiving or a couple of weeks before another holiday.
Look at when people get paid. If you have a major industry in your area, say a plant of some kind, if they get paid twice a month usually try to plan your sale at the end of the month or near their paydays.
Also, we always start early down here (usually cause it gets hot fast here in the south) when i have my annual sale, i am set up no later than 530 am.
Im planning my sale for this coming up weekend. Have a ton of baby/infant stuff to get rid of and a TON of clothes and toys.
i wish ya luck with your garage sale.