Set your parameters to 250 volts, four milliseconds, 0.6 millimeters, and three hertz.  Here I have a 14 karat yellow gold ring which I have cut some grooves in with a cut off disc to simulate porosity.  Now since porosity is really just not on the surface I'm going to fire at the first.  Now you can go straight down, I tend to use a little bit of a zigzag.  Now that it is clean I'm going to add my wire.  You can really choke up on the wire too now hold it like a pen like I said and fire directly down.  Again I'd like to use a little bit of a zigzag spun smooth it out this is how you add wire. You don't want to shoot too much directly on top of the water otherwise it will ball up.  Fire at the porosity and I do like to use a little bit of a zigzag pattern to clean it up then you can add your wire.  Again you don't want to have it just lying down, you want to have it, hold it like a pen and then just fire away.