Don’t get too adventurous
We recommend staying away from something too drastic, and make more of a subtle change. Going from a dark brown to a blonde is obviously a large and noticeable leap. It may look fantastic but we suggest adding just a touch of color first, for example going from dark brown to a lighter shade.
Give it a trial run
If you do insist on making a leap, then make sure you test out how it will look first. There are multiple ways you could do this. First, and the least technological way, is to go try on wigs. This will allow you to see exactly what the new color will look like, live and in person. The other way, if you are unable to do it, is to use some sort of software like Paint, or Photoshop, to imitate what you will look like with the new hair color. It may not be perfect but it will at least give you the gist of what you can expect.
At the end of the day, pick the color that works best for you, whether you do it yourself at home or get your hair colored professionally.