Here is a crash course on how to shop at Walgreens. For a bit more detail head over to the KCL's Walgreens 101. They also have a video that really helped me understand the policies.
Walgreens offers Register Rewards (RR) on some of their items. A RR is a manufacturer coupon (MQ) printed from a separate printer and is printed when your receipt is printed. At times you only need to buy 1 of somthing and you'll get a RR.
Now you know what they are, here's how to use them. Walgreen's coupon policy states you must have an equal number of MQ and items you are purchasing. Ex: you have 3 shampoos, 3 MQ's you clipped from the paper and you want to pay with a RR you gained from a previous purchase. This means you have a 3:4 ratio and you'll need to purchase one more item. This is where "filler" items come into the picture. Fillers are inexpenseive items such as a folder, hilighter or a piece of candy. The cheaper the better. At times you can get these items for as low as $0.10. Now your ratio is 4:4 and you're good to go!
Here is how to obtain the most RR you can. If an item is offering a RR when you buy only 1 of them, you can not buy 3 all at once and get 3 RR. Ex: Buy one lip gloss for $1.50 get a $1.50 RR. You can buy only one at a time to get the RR. This is why multiple transactions are done. You can do 3 separate transactions and walk out with 3 items and 3 RR. *Important* You can NOT use RR from your first transaction to pay for the same item on your second transaction, it will not print another RR. Ex: You gained a RR from your lip gloss purchase and you want another one. When it's time to pay for the 2nd gloss, don't use the RR you gained from purchasing your first gloss, a RR will not print. I hope I haven't confused you.
If you have ANY questions please let me know. You can actually make money at Walgreens with RR. Ex: lip gloss $1.50 and get a $1.50 when you buy (wyb) 1. You have a coupon for $0.50 off the lip gloss. You pay $1.00 oop (out of pocket) and you leave with $1.50 in RR which you can use to buy your next great deal! Watch what the RR say though. If the lip gloss is a Proctor & Gamble item (the RR will say what it's from) you can not use that RR to buy another P&G item and expect a RR. Now I've really confused you. Please post any questions you may have! :)