Buy 1 get 1 with % off

I would like to set up a coupon where if someone buys ONE product they can then get 20% off additional quantities of that same product.

I set it up with buy X quantity is 1, and get Y quantity is 1. I do not want them to have to buy one to get one of each, which is the way it's working.  If i change get Y quantity to say 100 it does not work at all.

How can i make it so if they buy ONE at reg price they get 20% off as many as they want additional?

I need this for products (and their variants) and a category.

I could not find example of this, can you please help?

Also i want it to take the discount % off ALL/ANY of the items, not just the first, or highest price.

Hello,

You can used value definition for this:

Function type: coupon

Value: (click on up/down arrow to open advanced value definition)

    Process type: step

    Qty                     Value

     1                        0

     2                        20%

Product: select it