Recommended DIY gray hair dyes

As I get older, I have so much gray hair. It’s a hassle to go to the salon every time, and getting root touch-ups every 3 to 4 weeks felt like a waste of time. After trying various gray hair dyes, this is the one I’ve settled on about 4 years ago. First of all, it doesn't smell. You know how dyeing your hair usually leaves a smell? This one doesn't have that kind of odor. Also, it’s super convenient because you just apply it and rinse it off after about 20 minutes. The price is great too! It’s a simple dyeing process that feels just like shampooing.