Did you know that you only have 7 minutes to get the color right after you've mixed it? Yes, you read right! You have 7 minutes to apply the color to the hair and once the 7 minutes are up, you need a new formula. Yes, you read right again!
Measuring and timing gives you more structure around achieving your end result, which is getting the desired color your client wants. Make it point to use a timer, so you're not playing the guessing game, because you may not get it right the first time. You don't want to waste your time or your client's time because you have to go back in for a second formula making moment. Aaaand... you don't want to waste product either.
Remember y'all time is money!