I started by put tape all over the piece of glass I had, this was a free drawing so I decided to do a seahorse
|Look at the knife there. It a signal of that poor tape's destiny|
Here's a detail from his face, notice the little pieces of tape left in order to respect the shape
Once you're don with the knife, the glass is taken to the etching room (which doesn't take more than 5 minutes) and here's the result:
Now you just take all the tape off the glass and voila!
I'll show you more of etching next time!