Start with flavour
Some recipes benefit from an oil with a noticeable aroma, while others need a more neutral background. Consider the ingredients and the final taste you want.
Consider the cooking method
Tempering, shallow cooking, sautéing and frying place different demands on an oil. Follow appropriate cooking practices and the directions provided for the product you are using.
Buy a practical pack size
Choose a pack size that suits your household usage. A size that is consumed within your normal cooking routine can be easier to store and manage.