I have two rules when talking to muggles about my lights:
1. Let them ask the questions. Info dumps are not fun for anyone, let alone about an, in their minds, “simple ‘make-the-dark-bright’ stick”.
2. If asked about how do you know so much about lights or why you have more than one torch on your person, never, NEVER say you’re an “enthusiast”. Instead tell them you’re a collector. It gives you way more leeway than you may think at first, believe me - everyone I said this to went “alright, cool” at most, no funny stares.