My job here at Groupon Coupons involves finding the best sales, promo codes, and shopping tricks, then sharing them with the world. After a year on the job, I can say finding deals is part science, part art. If you're reading this, you're probably already a savvy shopper. Want to take your discount-finding game to the professional level? I put together a few tricks my team always uses when we're looking for ways to save.

Sign up for email lists.

This is the first thing we do when we're looking for coupons and promo codes. Many stores will send out exclusive email codes to their subscriber lists—and sometimes, you can't even use them unless you're signed up. Plus, most places will send you a special coupon just for signing up. For example, if you sign up for emails at the bottom of the Saks OFF 5TH homepage, you'll get a coupon for $30 off a $150+ order. If you don't see a coupon within a day or so, check your spam folder. Many newsletters end up there on accident.

Do a quick search.

Some companies publish their promo codes on their websites and send them out via email newsletters, but others play a littler harder to get. They'll mention codes on the radio and sneak them into social media feeds. We do that searching for you—plus, Groupon Coupons even works directly with stores to get exclusive promo codes that aren't available anywhere else. So unless you check here, you won't find them. Moral of the story? Search for codes on Groupon Coupons, or give it a quick Google.

Leave things in your cart.

It's a classic tip for avoiding impulse buys: add something to your cart, then walk away for a day before going through with the purchase. But it's good for more than cooling your heels! Some stores (we've seen it with shops including Carseat Canopy) will send you an email or a text reminding you about your item—and include a promo code to make sure you come back to complete the purchase. It won't work all, or even most of the time, but it feels so good when it does.

See if you can stack.

Not all coupon codes work with sale prices, and many sites will only let you apply one coupon to your order. But the deepest discounts come when you're able to stack savings. Look for codes that work with sale items to give you an even bigger percentage off. Also, don't assume you can only use one code per order! Sometimes, you can apply multiple.

Go mobile.

Sometimes, companies promote special deals you can only access via their app or mobile site. For instance, Expedia has a $25 off $100+ promo code that's only valid on your first in-app purchase.

Join the club.

Sometimes, stores have loyalty programs that are separate from their basic email sign-ups—like the Neiman Marcus InCircle program or the Hotels.com Welcome Rewards program. Membership usually comes with exclusive perks, like free shipping on certain orders, in addition to letting you rack up rewards.