This game is great fun to play! You really made use of the one-button mechanic which we had to use, out of curiosity, what game engine did you use to develop this if you used any?
It did take a rather long time to load this game and there are a few things which are odd to me.
The quality of the loading screen didn't match the style of the game, why is the loading screen a science bubbly thing in blue and green and the rest of the game black and white with stickmen? I feel like some chopping scissors in black with a white background would've been a better loading screen for this game.
Great job on the cover image, I like your use of inverted colour and gradient and glow!
I really like the soundFX used for this too, it adds some comedy into the game, and it reminds me of those little hairdresser minigames I used to play on GirlsGoGames.com
Your use of the one button was great, holding it down to switch between the two, although I feel it would be more accessible of a game if you were to change this from b to the space bar or mouse button, since a child could play this who doesn't know how to read for example, and these are the most common buttons which are used in small minigames.
Perhaps you can try and implement an arrow which points to the object which is being used, since making them glow 2 different colours is a bit confusing.
Another thing, making some of the hairstyles didn't make sense! But that's okay, just a nitpick, for example, cutting the hair super short and then growing it to make a ponytail? xD