I used a trade triple for a few years. Mostly two sections and the third here and there. It was a bit too big for me to handle but I often had it near full for several regulars.
I was never one for having more than one person putting up a ladder, or moving it about. Things get complicated with two especially when it is up and needs moving.
I would stand facing the left stile of the ladder (so to the side of the ladder). Using my left hand to hold the ladder upright and my right hand to lift the top section up as high as I could. I would do the same for the second section.
With the bigguns it is easier to bump it up the wall, to minimise damage to the wall set the ladder at a steep angle (close to vert as you feel happy with) as you slide the sections into the higher or top box. Remember to set it properly before heading up.
A big ladder like that can be hard to move and the temptation might be to ask a mate to help move it, but i always felt safer moving it around alone. I Always had a clear plan of where the ladder was going, and also made sure that the path was clear of crap. Move the ladder to the wall so it is close to vertical, stand and face either stile and grip a lower rung with your L/R hand and the stile with the other. Which hands you use for which depends which way you want to go.
Simply lift the ladder to vertical and head offto the next window. If the next window is a way off or round a corner you may want to have a rest half way, I would be sure that the ladder has a place to go, preferably near a pipe to prevent it slipping in the breese.
There are a hundred and one little tips for moving and extending a big ladder, and only exp will find them all. There are also a hundred and one ways for it to go wrong, and knowing those is handy.
One that springs to mind is, make sure the ground is flat enough where you are taking it. I remember a long set where I got to where I was going and couldn,t get 4 points of contact. I couldnt leave the ladder there while I looked for a choc so I had to heave it half way back agai to make it safe.
Better still save your back and get a wfp.