It really depends on your personal preference and the specific needs of your hair. Here are some things to consider when deciding whether to air dry or diffuse your curly hair.
Air drying: Air drying can be a good option if you have time to let your hair dry naturally and if your curls are relatively well-defined. To air dry, simply scrunch your hair with a leave-in conditioner or curl defining product and then let it dry on its own.
Diffusing: Diffusing involves using a hair dryer with a concentrator nozzle to dry your hair while scrunching your curls with your fingers. Diffusing can help to enhance curl definition and reduce frizz, but it can also cause your curls to become dry and frizzy if not done properly. To minimize damage, use a low heat setting and avoid holding the diffuser in one spot for too long.
Ultimately, the best option for you will depend on your hair type and the look you’re trying to achieve. Some people find that air drying works best for their curls, while others prefer diffusing. Experiment with both methods to see which works best for your hair.