I personally use a modified accordion file system. First of all I buy at least 3 newspapers every week (one per family member) just for the coupons so I can stock up on great deals. To file the coupons, I keep the entire insert intact, put a sticky note with the date on the front, and file in the correct folder. DONE!
When it’s time for me to make my grocery list, I make note of what coupons are listed on my matchup sheets. Go to that folder, pull that ad, clip the needed coupon, and file the remaining ad for future use. I also have printed (internet coupons) and store coupons that I use.
Then I put the coupons I’m going to use in an envelope labeled “USE”. All coupons that I clip and end up not being able to use for whatever reason get refiled in the “CLIPPED” folder where I have different envelopes for different categories.
If you have any questions, let me know and I’ll be happy to help you out the best I can.