I can build pretty much any practice area I want. I am going to build a wood deck and a rail. What ever I make the rail out of will be adjustable so I can find the height I want.
My question is; why not two rails? Or am I trying to reinvent the wheel?
You dont NEED anything to help you get started, but the rail will definitely help, i can see two being slightly counterproductive though, save your space for the epic trials course you’ll want once you’re done learning 
Hi, Michael. The rails seem to work well for some. You may want to watch, however, that they don’t become a crutch that holds you back on pushing off into the great unknown.
I’d suggest, if you use rails to get comfortable with the full pedalling action, you alternate sessions on there with sessions of pushing off from a wall / doorway / fence with no supports to grab hold of.
Cheers,
Eoin
Hahaha at first I thought you meant a rail to grind, but then I realized you wanted a skinny rail for trials, but then I realized you want a rail to hold while you learn to ride :p.
I personally didn’t use a rail to learn, but from what I’ve heard a rail on either side of you is great because you won’t lean more to one side than the other.
Unicycle riding does not require a construction project! 
Go find a good location with a fence or rail and use it for a week. Then you should move on and learn to ride unassisted.
Are you sure? It was my understanding that everything required a construction project.
Thanks for all your help. I heard loud and clear I will learn by doing.