Erecting scaffolding structures can be tricky with 2 people, but on your own its almost impossible. Once you’ve got the 4 vertical poles of the first bay up things get easier.

I've cut most of my vertical poles to 4m using an angle grinder.
Double arm transoms make it getting your ‘ledgers’ at 90 degrees to the ‘standards’ easy, getting the standards vertical and spaced properly is the difficult part.
I’ve made it easier to assemble a tower on my own by getting 2 H pieces of scaffold welded together. These 2 pieces can be joined with 2 double arm transoms which guarantees a level and correctly spaced base.

Welded Scaffold Base
I can then put sleeves on each of the 4 short vertical poles and then fit a 4 meter pole into the top. this make it easy to construct the first ‘bay’ on my own.
The height of each of the short vertical poles is 75cm, the standard height of a table tennis table is 76cm. So this scaffold base can double up as the base of the table tennis table!
Because only the 2 ‘H’ sections are welded the base can be dismantled to fit through the doors.

Welded scaffold tower base doubles up as the table tennis table base.
Always have your scaffolding inspected by a qualified scaffold erector before using the scaffolding.