To apply your coupon please refer to your welcome email that has the coupon code. Enter the coupon code into the coupon box in your shopping cart on your next order over $50.
Please note, this will become available to Trade customers once you are approved.
If you have not received your welcome email containing the coupon code within an hour of signing up (or being approved for Trade), please refer to here to troubleshoot.
For further information on how to apply a coupon code please refer here.