Users can manage their stocks by activating 'this product has stock' check box when uploading the product.
You can manage the stocks numbers quickly via Inventory Management. Steps are below.
Manage > Inventory > Start Editing
1. Click Manage and select Inventory.
2. Select the product that you wan to update or search using the Search Box.
3. Fill in the next stock count in the box provided. Use the 'Low Stock / High Stock' filter if necessary.
4. You can also update your product that have variant by using this method.
5. Note that items that aren't activated their stock checkbox won't be appearing here.