Even before ordering my wheels, I had begun to read about bicycling safety. I knew what hand signals cyclists are supposed to use, but little else, and I needed to learn all I could. Googling just about anything brings up scads of entries, and that is how I found Frank 'n' Fred in the Bicycling Life site.
Riding even a three-wheeler requires a certain amount of work from the arms. The leg action can make the trike swerve from side to side. I made this adjustment quickly, fortunately.
At the time, I had been walking to and from work for years. It was about a mile each way. All that walking apparently helped to pre-condition my legs for the trike.
The manual that came with the trike warned against trying to lean the trike into a turn, which can cause one of the rear wheels to leave the ground and result in a spill. Since I hadn't been riding on two wheels prior to getting the trike, this was never a problem for me. If you've had to give up riding a BI-cycle for some reason and want a TRI-cycle, keep this in mind.
Of course I had some trouble with flats. After about eight of them in fourteen months, I got tire liners. I use them with my hybrid and road bike now, and they definitely help.
In the long run I wound up putting that poor tricycle to uses that it probably wasn't meant for. When I first got it, I never imagined I'd end up doing half-, metric, and full century rides with it. By the time I let it go in June 2013, it had over 11,500 miles on it. If one day I can't ride two wheels any more and have to get another trike, I'm going to shop around for an industrial-strength model.
"Valkyrie" and I had some great times together during those years. The biggest highlights were the century and one rare, windless morning when I somehow managed to push that rig 12 miles in just short of one hour. Ah, memories!