Glass Tile Installation

I recently purchased 1x1 glass tiles that come on a 12x12 paper mounted back. I have read that it is recommended to use a substrate, is this necessary?

The tile is for a kitchen backsplash that is not a moisturous area. Can I apply directly to the dry wall?

It is a wrap around wall, what is the best area to begin installing the tile?

Thank you for your help!