Beware of the free gift with purchase. Shoppers equate added value with a discount. Even if the reality is that they're spending more to get a freebie they wouldn't have purchased otherwise and might not even use. Consider the item and the free gift individually to make sure each works with your shopping list, and that the price is competitive.
A purchase limit increases the likelihood you'll buy at least one and with higher limits, probably even more. That implies the deal is so great that, if not for the cap, shoppers would be filling their carts to the brim. Resist the impulse to buy more than you really need.
Stores are sending daily emails, and often several a day when big sales end. That barrage is like spending all day in the mall, every day. The longer you browse, the more likely you are to buy. Don't open retailer sale-mail unless you were already looking to make a purchase from that store. Otherwise, delete it unread.
You'll often see ads that emphasize how much you're saving on a purchase, and then point out the new price in tiny print below. When the deal is the first thing you see, the price becomes almost an afterthought. Make sure you conduct a price comparison to find the real best deal.
People assume they can game the system by spending just what they need to now and later. But stores use this tactic to steer you back in stores when they have new stock or other enticements that increase the likelihood you'll buy more than you planned. In this tough retail environment, stores can't afford to stop offering discounts, so base your buying on current discounts only.