My 'first time' was "Hollywood". My friend Ken and me decided we would shock all our friends and go in costume so we planned it all secretly.
Ken is about 6'3" and stocky so you can imagine what he looked like in full Liza Minelli 'Cabaret' costume: fish-net tights, suspenders, silver bodice, cane, top-hat and tails

I couldn't make my mind up on a costume. I knew I didn't want to dress up as a woman, but nor did I want to do something relatively easy like a tuxedo as a suave James Bond.
The issue for me was it would be my first time dressing up in public and I knew I'd chicken out if I didn't do something that really pushed the boundaries of my comfort zone.
Being a fan of cartoon animations I somehow decided on going as Mowgli from Jungle Book, which would avoid me having to get frustrated trying to create a complex costume. I had to colour my blond hair jet black to make it look authentic. My hair was quite short back then so it didn't quite look like Mowgli's 'mop' but it was okay. I made a loin cloth from a piece of calico left over from a roman toga party I'd held recently.
I looked rather naked and it was hard to tell who the character was so I had a moment of inspiration and decided to 'wear' the 10-foot long green snake I won at a fairground. Usually he hangs from the ceiling at home. So, Ken and me did some threading of cotton and buttons to ensure the snake's coils hung uniformly, and pinned the head so it was peering over one shoulder.
We were all nerves on the drive to the pub in costume, hoping not to be stopped by the cops and have to explain our dress - especially as I was just in the loin cloth! At the car-park I got 'into' the snake and off we went.
I can still remember the silence that descended the moment I walked through the door, as everyone stared. I almost turned and ran but then I saw all the smiles and grins and heard the 'wows' and I thought, "Yeah, I can do this!". Once I'd got used to the feeling of being almost naked I found I was enjoying myself, and certainly getting a lot of flattering attention from some of the hotties too

The funniest/scariest/worst part was that the drag queens seemed to decide en-masse that I belonged to them and would surround me and keep on trying to grope me under the loin cloth. I discovered that by crouching down quickly the snake's coils would trap their hands and protect my innocence
I think there were about 12 people that dressed up, the rest were boring sods! There was a vote mid-way through the night for best costume and I was amazed when I won it. It made me realise though that the entire thing had been worth it and people didn't think I was stupid.

On stage with the runner-up

Xander, me, Ken and Steve.