How and when to tell a girl you have herpes

I have HSV-2. I don't think it's a big deal having had it for about 5 years and knowing that the symptoms are minor, but obviously it's something that needs to be discussed.

How though? What is the best way to go about it? I don't want to shoot myself in the foot whether I tell them or not.

Or I could go full Machiavellian and say that I've been tested clean and they got it from someone else.