If you wish to enable batch tracking in bulk, click this article to learn how. To enable batch tracking for individual product variants, keep reading!
New Products
To enable batch tracking for new products, create a new product as you normally would and you will see a toggle called Batch Tracked. Click to turn on this feature.

Input the relevant information and create new product. Next, click on Manage Batches. Here, you can assign each variant to a batch for tracking. After assigning all the batches, save changes. You will no longer be able to edit the batch quantities other than by creating a stock adjustment or purchase order, to ensure that there is a record when adjustments are made to batches.
Existing Products
To enable batch tracking for existing products first select the product in your Inventory. You will be taken to the Product details page. Click on Edit Product Details.

On the edit product details page, scroll down and enable the toggle to turn on batch tracking. Save the changes.

Next, click on Manage Batches.

When managing batches you'll see the stock level of each of the product's variants, for each of your stock locations (locations as tabs running across the top of the page and the unbatched stock represented in red on each tab).
To assign stock to a batch, select the quantity and enter a Batch ID. If needed you can also add an expiry date. You can create additional batches using the Add Another Batch button, however, each batch ID needs to be unique.
Once you have assigned all variants to their batches, click the green Save For Location button.
If you have already assigned your stock to a Batch ID, you will not be able to make further changes. You will see this error message on your page:
These batches will now be tracked based on sales orders, purchase orders and stock adjustments they are tied to. To see which documents a batch is associated with go to Inventory > Batches > click the batch you would like to view.
If you would wish to create a stock adjustment for batch tracked products, click here to learn how.