Suave Dry Shampoo
I've used this brand once. Some people absolutely LOVE it, but it wasn't for me. There is a distinct scent to it, one I wouldn't necessarily describe as pleasant. The biggest issue I had with this one was that it left a slight residue in my hair. Yes, I brushed out the white powder, but my hair still felt grainy to the touch. If you don't mind either of those, it is a wonderful budget option, and it did add quite a bit of volume to my hair!
Let me start by saying, the smell isn't nearly as wonderful as some other products. It's not bad per se, just not fantastic. It eliminates some oily sheen, but not all. If you're only using dry shampoo for a bit of volume, or to get rid of some oils for a quick meeting (face-to-face/Skype) before you hop into the shower, or one last errand after the gym, this is a great, low-cost option. For all day use, you'll find yourself needing to reapply.
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In a pinch, Johnson's Baby Powder is the go-to. I bring the little 3oz one with me on vacation and just put a little on if needed. Cheaper than a travel size dry shampoo, easier to find, and great in a pinch, just puff some on your roots, brush, and go! This one is the winner in smell too, ha!
What's your dirty (clean??) little secret?