To redeem a promo code, go to splice.com/plans. Make sure you are selecting the correct plan that corresponds with your promo code, such as Sounds+ vs Creator.
Once you've selected a plan, on the next page, select the billing frequency (monthly or annual) that corresponds with your promo code offer.
Then, input your credit card / Paypal information -- the promo code entry field will not be visible until you've added a valid payment method.
On the following page, you can enter your code in the "Enter promo code" field here:

