I would like to try to practice on a tiered cake in a Damask design.  I am going to purchase some stencils and wanted to know which would be easier.  To air brush the cake or to use royal icing.  I would really like to know if the royal icing would pop better since it will not be flat against the surface like the air brushing.  I would appreciate any tips and help.  Also how would I get a very dark black royal icing?  I have never used royal icing before.  Thanks!

global sugar art has some great videos on that