You can check and edit your inventory at any time through the Profile page.
To find this, click on your username in the top-right corner and select ‘Buy & Sell’ from the drop-menu, then click Inventory in the left column:
From here you can edit or delete single items, or click in the check box next to an item to perform bulk actions, such as activate or deactivate:
Deactivating an item in your inventory will remove it from the marketplace, so it will no longer appear for sale to other users. However, you can relist it at any time by simply marking the item as active again whenever you choose.
Note: You can check the listing status of an item in the Active column: