Note: In order to create redemption codes, You need to create a listing first. 

To know how to create a listing, Click Here.

Step 1: Go to 'Listings' and click 'Manage' on your desired listing.

Step 2: Click on 'Codes'.

Step 3: Now your first batch # 1 is already created for you, you can download the file by clicking the link 'Download CSV' and using it on AppSumo.

If you want to create more codes batch, click on the plus icon on the top right.

Step 4: Click on 'Yes, Generate more codes' and continue generating more codes as needed.