A. Click the green + button. The listing will be added to your "Make trades" tab.

B. Once you click the green + you'll see the average market value, have the option of making a cash offer for the game , and/or assign a hidden value to the wanted entry. Hidden values allow you to quickly make trade connections and don't involve money.

C. If you fill in the entries, you'll have the option of removing them quickly by clicking the red X.