If you are asymptomatic and have herpes 1 how do you know when you are most contagious? could i ever kiss again or have sex without a condom?

You cannot know for certain. However, in absence of visible outbreaks, transmission of oral herpes is rare, either by kissing or by oral sex. Half of all adults in the US test positive for HSV1, and most never transmit it to anyone else. The most important thing is to be alert for outbreak symptoms and avoid contact of that body part with other persons until healing is complete.