How to Use Dry Shampoo on Fine Hair Without Coating the Ends
When your part looks shiny but the ends feel clean, treat the roots as a small target. Start with one parting and check the result in daylight before applying more. Dry shampoo absorbs some surface oil between washes; a regular shampoo and water remove the build-up.

Part the hair where it actually looks oily
Ciblez la raie ou la frange
Give the powder its contact time
Laissez agir avant de brosser
Know when to wash instead
Repérez le moment de laver
Source · American Academy of Dermatology