Despite Barskor's incomprehensibility, he's essentially correct. Develop a touch-range (+1 Reach, like rasmusnicolaj suggested) damaging spell, cast it, tie it to a sustaining focus 'hilt' ... and there you go. In SR2 we used the Anchoring rules then (which have since been severely emasculated) to enable an actual on/off action that you didn't really need to worry about.
Alternately, and here's the more likely, less Drain route, go with weapon foci swords. And mystic adepts.