Separate your head of garlic into individual cloves. Peel the cloves of garlic, then cut into uniformly-sized pieces using your preferred method (see above for description of methods: mortar and pestle, food processor, chop, slice).
Add oil to a small pot and heat to medium heat. Once the oil is hot, add a test piece of garlic. If it bubbles up in the oil immediately, the oil is ready.
Add the rest of the garlic to the oil. It should bubble a lot when initially added. Stir the garlic often, and watch it closely. As it becomes crispy, the oil will bubble less.
Once the garlic starts to become a golden color and the oil bubbles less, scoop the fried garlic out of the oil. Err on the side of less color than more color, as the garlic will quickly go from golden to burnt.
Let the fried garlic drain on a paper towel. Strain the remnants of the garlic out of the oil and save the garlic oil in an air-tight container.
Notes
See Key Tips section above for more detailed information about how to make perfectly crisp fried garlic without burning it.