How to Use a Diffuser

Revlon RV544 hair dryer
Q: I would like to know how to use a diffuser properly. I bought a new hair dryer, with a diffuser attachment. What is a diffuser for and how should I use it?
A: The diffuser attachment for your blow dryer is a device that breaks up the flow of air coming from the nozzle. The attachment converts the flow of air from a strong blast of air to a gentle aura of airflow that is gentle to the hair. This is ideal for people with curly hair who want to dry their hair without lessening the curl.
You've surely experienced the blast of warm air from a hairdryer and seen how it pushes and whips the hair. This strong airflow can pull the natural curl from the hair, and is why, when combined with a brush to create more tension you can straighten curly hair using a blow dryer.
The diffuser attachment keeps the hair from being roughed by the airflow, allowing the hair to be dried without stretching out the curl.
It's also great for fine hair types to prevent over-drying the hair. Simply use the dryer with the attachment as you would use it without it for normal hair. But like with any blow-dry style, try to stop short of "fully dry" unless you plan to use another heat styling tool afterward.
See also:
The best blow dryer
How to blow dry hair
Hairstyling tools: tips and tricks
How can I get more volume to the roots of my hair when using a diffuser?