If you don't know about dry shampoo yet, I accept all forms of gratitude. Dry shampoo will change your life. There are few heads of hair too far gone for Bumble and Bumble's hair powder. (And it's amazing when you need an updo to add that traction and texture needed for teasing and bobby pinning.) You simply spray at the roots, let dry and brush out. I then advise a heavy bit of teasing to keep hair off the scalp. In fact, if you're not teasing your hair every day, I advise you start immediately.
The beauty of Bumble's hair powder is that it also serves to cover roots. It comes in brown, black, blonde and white so no fear of having a George Washington wig look. It blends with hair and covers those grays that are starting to come in because you were too busy to make that hair appointment. Bath Haus in River Ranch has a variety of Bumble hair powder (and other Bumble products, which in my humble opinion are the absolute best hair products on the planet save for Big Sexy Hair's Spray and Play, which can't be beat in the hair spray department).
The world's best teasing comb I've found is like five bucks from Sally's. It's a three row comb and does wonders for taking flat hair to another level. I use it in combination with a more traditional teasing comb with a pick that smoothes after I get it good and high.
Another dry shampoo use – post workout. If you're the fitness type, it's great for freshening up your look post pilates. Because even if you have time to wash your hair, you'd rather be doing something else.