Sure,
Firstly I used a little bowl with a lid to contain the hot solution. The solution itself was a mixture of vinegar, lemon juice and a spot of dishwasher soap.
I don't normally use lemon juice but I was running very low on vinegar. The dishwasher soap is there to break up the surface tension in the solution so you really need a very small amount so that you do not reduce the strength of the solution.
After you have made the mixture heat it up, I use the microwave as it only takes a few seconds.
Make sure that the blade itself is hot, I use either the flame hob or place the blade on top of a metal radiator.
One both are hot, then using whatever you want, cover the blade in the solution. You will have to keep heating up the solution and re-applying as having a hot solution is very important to the success of the etch. Once you have finished neutralise the acid. I use baking powder.
Polish the blade using a non-abrasive polish.
Thats about it really, the longer you do it for the more prominant it will become, but if you etch for too long the pattern will become muddy.
...looks like I went on for a bit there... well thats something for you beginners out there.
Will