To change the quantity of stock available for a particular item, follow the steps below:
1. Navigate to the Manage tab of your Dashboard and select 'Store'.
2. Open the product in question and switch to the 'Variants' tab.
3. Select the 'Advanced' button located beside the save and delete button. Once this has been selected, an option called 'Stock Quantity' will appear.
4. Enter the stock quantity and click 'Save'.