Dilute DNA plasmids with distilled water
Buffer EB is simply 10mM Tris buffer, ph 8.5. I think you are worried about the ions present in your electroporation. There are two things to consider:


What is the concentration of your DNA and how much do you need for the electroporation?
In which final volume is the electroporation taking place?


In my experience, usually you add a very small amount of DNA (a few microliters) to 100, 250 or 400µl (depending on the cuvettes used) final volume. Here a tiny amount of Tris does not interfere or cause a short circuit.