Ready for the 'chain gang'...

I have been reading the forum and studying various other instructions and am about ready to try to try to put the chain on my MB. It is upside down on the picnic table as that is where it was positioned when I was putting on the sprocket. It is easier to get to upside down since I have no one to lend a hand. Should the bike be right side up on the floor/table for the chain installation? Where should I try to put the back wheel? It is as far back as I can get it, but I haven't hit it with a rubber mallet yet. The instructions say the pedal chain and drive chain should be equal lengths. Most pictures show the tensioner mounted.
All suggestions and advice much appreciated.
Pedal Pusher

Sounds like you have a single speed bike. The chains will never be the same length to the link, but I get what they are saying.
They are just trying to tell you that if you are going to slide the wheel backwards, to tighten the chains , the "shorter" chain will get tight first, leaving the other chain loose.
If you are using the idler or tensioner, I would not even worry about it and just carry on as you would with any geared bike. The new chain will stretch more than the old chain that came with the bike so the tensioner will make your life easier.