After certification, my first dive trip was to Playa del Carmen and Cozumel. I spent a week diving cenotes with an instructor, but once we got to Cozumel I was on my own and doing boat dives for the first time.
On my first trip out, I was pretty pumped but also pretty nervous. As luck would have it, I was seated near the bow but entry would be giant strides off the stern. This meant I had to walk nearly the entire length of the boat--maybe 20 feet!--fully suited up with both my fins and tank on while the boat rocked from side to side. Yikes.
When my turn finally came, I stood up and started shuffling, a few inches at a time, towards the rear. I looked up at some point and the entire Mexican crew was looking at me like "wtf?". I'm sure I turned bright red with embarrassment but just put my head down and shuffled as fast as I could. After what seemed like forever, I finally made it to the back of the boat and into the water.
After my son was certified a few years later, I took him diving in the Keys. I had promised his mother that I would be especially diligent in my supervision. Our first trip out, I went over his gear with a fine tooth comb, making him show me what went where, how things work, etc, before finally letting him hit the water. Then I followed--without my mask and my fins. Oops.
He thought it was hilarious and every now and then he'll be sure to bring it up when we go diving.