I usually use the "made especially for you" type that I can get at the quilt store. I just write the name of my quilt, who it's for, anything special about the reason for giving the quilt, like for a wedding, my name, the date, and where I live and applique it on the back. If I don't have a pre-made one, I write all that on a solid fabric and applique that instead. There's no wrong or right way to do it, except to make sure that whatever writing implement you use is permanent. I also press with a hot iron to be sure the ink is set.