Does shaving the top layer of your gums down leave a scar or does it heal and look naturally?

You may or may not show scarring/colour discrepancy depending on the nature of the graft and the colour of the graft tissue versus the colour of the gums where the graft was placed. Hope this helps. 

The degree of discoloration you can
expect from the "gum shaving" procedure can depend on a few different
things. In general, both the natural gum and the graft should heal and look
relatively natural. If uneven discoloration is a significant issue, you may be
a candidate for gum bleaching, a procedure that's offered by many aesthetic
dentists. I recommend scheduling a consultation with an aesthetic dentist near
you to learn more about your options. Good luck!

Sometimes grafted gums appear different in color and texture.  Most of the time the surface epithelium (skin) can be removed allowing the body to heal, leaving a new layer that more closely resembles the adjacent tissues.  This is not always possible, so it depends on the type of graft that was done, but is always worth the effort if the tissues currently make you self conscious.It is not as uncomfortable as one would assume.  Depending on methods, thechique and materials used, healing is usually quick and uneventful.