A Gift Card can be sold from the Sales section, or from the Gift Cards section (see How do I sell a Gift Card? (Gift Card view))
Please note, when using the iOS App, a the Gift Card must be first be created, before if can be added to a Sale, see How do I sell a Gift Card? (Gift Card view)
Tap + Add Product in the Edit Sale box, and select Gift Card :
Select from the list of Gift Cards - which have been created but not yet sold:
The Gift Card will now show up in the Products section:
Proceed with adding any required items and payments to the Sale (see How do I add a Payment to a Sale?)
Then close the Sale
To email the Gift Card see How do I email a Gift Card?