How do I redeem my Valve Store coupon code?
The Valve Store may offer promotional coupon codes for discounts and special offers via email, social media sites, forums, etc.
To redeem the Valve Store promotional coupon, you must create a Valve Store order at store.valvesoftware.com/
On the "Review and Submit Your Order" page, enter the coupon code in the box labeled "Coupon Code" and click "Apply".
Note: Your discount will be visible directly under the Item Total line in the review.