The color of the flake you use is totally up to you. The normal light blonde flake are what I have been using for sealing and it puts a light golden tint to the work. You could of course adjust it by adding amber flake or switching to it all together. Most of the shellac that is premixed and is in spray can form is the blonde flake. You will need to experiment a bit to find what color(s) work for what wood. As I mentioned it generally is the builders preference. Like mentioned shredding the flake will make it dissolve faster.
DW