Feel free to use whatever hook size you like. I tend to use H, but it really does not matter. 20 stitches ends up measuring to be about 3 inches for me. You can make your ribbon as big as you like, but I like to make smaller ones. I pin mine to my backpack to show support for our troops and/or send them in the mail to my cousin serving in Afghanistan with the Marines.

Also, chose whatever color you like for your project. I use yellow for the two reasons above. Use pink, red, blue, green, black, etc. to coincide with your cause.