This video covers how to render lard using the oven method. Similar methods can be used to render chicken fat, beef tallow, and other rendered fats though there can be some differences.
In general, it is best to start with either fat around internal organs (like kidneys) or back fat (which is what I used here). You should remove large pieces of meat and the skin to the extent practical. The meat can be used in other dishes, and the skin prepared into pork rinds if you are adventurous.
The method is fairly easy: cut the fat into small cubes and spread in a baking sheet with walls that will hold in the fat. Bake in the oven at around 150C/300F until the fat is well rendered and the cracklings are beginning to become crispy. If you want a stronger flavor, bake at a higher temperature. If you want a more mild flavor, bake at a lower temperature.
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