It becomes first nature, don't sweat it.

I've only ever had one experience that wasn't pleasent.
I was at a small grocery store I always go to, they see me kilted all the time. The young lady working the line wouldn't make eye contact with me and she turned bright red. There was a delivery man behind me and I knew what was up. I asked her if there was a problem and she said "so and so just cracks me up" I turned and looked at him dead-pan, no expression what so ever. He quit joking (at me) and looked down at the floor-he wouldn't even make eye contact. I took my stuff and walked out all puffed up like I owned the store.

Confidence-walk with pride.