In order to put a used gun on layaway, you have to be a Team Buds member and also it has to be available for layaway. You should see whether it is below the "Add to Cart" button. If you go through with the process, you just add to cart (if available for Layaway and you are a Team Buds Member) and then click beside "Layaway" for payment method when going through the process.

You have to be a Team Bud's member and then when you buy the gun and payment method comes up just click on the 90 day layaway, after you purchase gun with lay away it will tell you how to make your first payment and how much it will be