You can get genital herpes from intercourse, rubbing genitals together and from oral sex. Possibly it’s also transmitted through shared towels.
It’s very contagious. When you have sex once with someone who has blisters there is a 75% chance that you also get it.
From the first signs till the wounds are gone you must avoid sex, also oral sex when you have herpes around your mouth. The liquid from the blisters is very contagious.
A condom protects you a little, but is not really safe.
When you have sores you must keep them clean and dry.