The 'MJM' is the bit you did? If so thats ace!
Any tutorials about...?
that's the bit - I found the tutorial on British blades but it's very easy
Mask off the bit you don't want to etch - include a fair amount of margin - I used letter transfers from WHSmith and insulation tape.
Get a 9V battery, two wires - attach one wire/terminal to the knife blade (not sure if polarity matters here) - a croc clip would help
attach the other to a piece of cotton wool soaked in salt water solution (over saturated to be sure)
Dab the wet cotton wool onto the mask - hold on. It will fizz - the cotton wool will start to go black as material is transferred from the blade to the cotton wool.
THe longer you hold the deeper the etch.
Beware - hold too long and it will etch "under" your mask.
Give it a gentle polish afterwards to bring out the design.
I have no idea if this works with stainless.