To sell tickets on StubHub you need to have created an account with StubHub and have your login information available.
You will find your tickets under the My Ticket Inventory tab. From there you can select the game date and tickets you wish to sell.
After selecting all the tickets click on the "Sell on StubHub" button.
A pop-up window will appear, so make sure all pop-up blockers are turned off. In the new window you will enter your StubHub login information and follow StubHub's instructions on how to finish posting your tickets for sale.