Re: blonde to dark brown for fall!
Hey, I was in the EXACT same boat a couple years ago. Blue eyes and all. I had an ash blonde colour primarily. Now, I was questioning whether or not I should do this myself, but then I thought it was such a huge change, I went to a salon. Go to someone you've maybe had before, or someone who is recommended to you.
Going from blonde to a medium/dark brown, the hair colour must pass through "stages". Blonde hair usually has very little pigment in its shaft. This means that when the hair is processed with a darker colour, there is hardly any pigment for the new colour to bond too - hense the "mousey" brown effect. In order for more pigment to be inside the shaft for the brown to latch onto.. you should have it processed, first, with a colour found in between blonde and brown. This usually is a reddish colour. This will fill the shaft with enough pigment for the bornw to latch onto.
If this was an at-home job, you could get a copper-ish colour kit along with the medium/dark brown one. Have an afternoon free so you can do this multi-step hair job. You would first apply the copper colour. Allow that to set for as many minutes as it says. Once you wash it out, try not to look at it.. haha, seeing the red colour when you want brown in the end, might be shocking.. but just remember that you're a couple hours away from brown! Now that the red is all washed out.. (and don't use shampoo while washing out).. allow your hair to dry for an hour or two.. this just dries the shaft out a bit, so that the brown can get into it.. without sliding off. After the couple of hours, prepare the medium/dark brown colour, and apply. Leave this on for the set time, and voila!
Because it is such a big change, I wouldn't have been able to do it myself. I just was told these steps by my hairdresser friend. I went to her to do it, and she was able to add a copper colour into the brown hair dye that she used.. so it was a one-step process. And whichever way you use (at-home or salon) don't worry about the copper colour.. once the brown is in the shaft, you won't even see that red again!
Good luck, and just to let you know, it was the best hair change I could have ever done.. I've kept it dark brown ever since!