I use a fine tip pen and write my name on the lower right hand corner on the back of my quilts. Many quilters have told me not to do this but rather make a label. The reason I do it with pen is because a while ago I saw a very old quilt with the quilter's name in pen on the back. It was so nice to see her writing and made it more personal.
I have made a few labels but mostly use a fine point Sharpie.
The quilts are very lovely!