Couponing is great! You can get a bunch of stuff for free but it isn't like the show Extreme Coupon. First step is to know your stores coupon policies, they will be on the web sites for each store.
Second, you need to get your coupons. The best ones are in the sunday paper of a city. I live in the outskirts of Denver so I get the Denver Post. The local small newspapers don't usually carry them. You can also download them onto your grocery savers card and there are numerous sites. The ones I like are, Couponmom.com,Coupons.com, Mommysavesbig.com and wow_coupons.com. You can get grocery, household items, pet, beauty and retail store coupons and print them off. There is also the way to go directly to your favorites brand web site. Betty Crocker, Kraft, CoffeeMate, you name a product will have a coupon...eventually.
Third, you have to read the grocery circulars and match coupons to the items you want that are on sale. Most store will take coupons. I don't know where you shop, but Kroger stores (Kroger, King Soopers, City Market) and Safeways will double coupons up to a dollar. Wal-Mart and Target do not. Although if you have a Target coupon for Charmin Toilet paper for $1.00 off and a manufactures for $0.50 off Target will give you $1.50 off the price.
Things too know...when checking out, always go to the male checker. They aren't as picky about coupons and sometimes you may accidentally have and extra one in your pile. They don't give it back, they usually over ride the register. Keep your coupons in a file folder according to the aisle route you take in the store. It is easy to carry and easy to match up with items that you didn't know are on sale.
I hope this isn't overwhelming. You will figure out what works for you. One the Couponmom.com website, she have video tutorials on how to do this.
Happy Couponing!