1. Go to Order page of Admin Panel
2. From upper right corner select reseller customer belongs to
3. Click 'Add new order'
4. Select customer from customer picker by Existing customer field (this should auto fill in all required fields, if not, add manually)
5. From drop-down list select product for domain transfer (depending on TLD you want to transfer)
   
6. Click 'Edit product data'
7. Put Name 'DomainName' and Value 'domain.tld' (replace with actual domain you are transferring)
8. Click 'Add new filed'
9. Put Name 'TransferAuthCode' and Value 'code' (replace with actual code)
10. Click 'Close'
11. Click 'Save'