Step 1: Locate the desired GNC coupon code and select "Get Code". A new page for GNC will open on the left side of the current page.
Step 2: Once you click the "Copy" button, a confirmation message saying "Copied" will be displayed, signifying that GNC's coupon has been successfully copied to the clipboard.
Step 3: While checking out, find the designated discount code box and proceed to paste GNC coupon code into it.
Step 4: Upon clicking the "Apply" button, the displayed discount amount will reflect the applied discount.