"I play a live action role playing game. It's like (insert game reference here) but we get dressed up and actually play.""I play a live action role playing game. It's big kid dress up and pretend."
Forgot the second part of the question. I don't ask them nor do I care what they think of my LARP Life. It's part of who I am, so that's a thing.
I always just say, "Imagine a roleplaying game or a story, but you're actually playing in it.", and I always follow up with a "And we get to hit each other with foam sticks." Honestly, I've always been as descriptive as my audience's interest in the subject. I've never intentionally hid or omitted the fact that I LARP.Most people, regardless of their opinion to LARP, have been respectful and ask genuine questions out of curiosity. I've had the rare few who look down on it, but I pay no heed to it. I've only met one person who thought things like LARP (He also included MMO's) was an indication of a broader social problem in the person, but without going into details, his position quickly crumbled. I have to give kudos to my mother. She used to see me off to events when I was 17, and now sees me off with my whole family at 34. She listens to the stories, the intrigue, the politics, the wars, everything. She is genuinely interested, and it's nice to have a non LARPing ear to bend about Realms. Like the unseen seer giving advice.
It's like Dungeons & Dragons, but we actually dress up like our characters. They almost always immediately ask about swords which I explain we hit each other with plumbing supplies :) But then follow up with how we have rules on the construction of them. Our families and friends have always been accepting of it being a major part of our lives. We even have work clients who inquire about the game when we see them.
I recently started just fliping open my phone displaying a pick of me LARPing and saying, "look how cool I am...". I take it in whatever direction it goes from there.
I usually relate it to improve theater.