Hi @GV123 thanks for posting in the Klaviyo community - great question!
The easiest way would be to auto-append coupons in your URLs so they apply automatically at checkout.
This article tells you how to do it for a Shopify Store.
You can link to your homepage and auto-append the coupon this way:
mysite.com/discount/CouponName (where CouponName is the name of the Coupon in Shopify for a static code)
mysite.com/discount/{% coupon_code 'CouponName' %} (for dynamic codes in Klaviyo - this would be the name of the coupon code for the unique codes
If you wanted to link to a different page, for example, a product page, you can use this format: mysite.com/discount/{% coupon_code 'CouponName' %}?redirect=/new-path but if there is a previous “?” in the link, you need to change it to an ampersand (&).
In terms of copying the code, my recommendations would be to make the text very big, and not part of a button, which is harder to copy.
Hope this helps!
Katherine