Here's the contraption in use, a seemingly random collection of lengths of steel poles attached to a winding wheel. (See Reference -4 May 2008 Heath Robinson/Rube Goldberg and you will get the idea )
This what you do: lift the sheet on to the top platform, it's a good idea to have selected someone to help you with this task, preferably someone about the same height and arm length. If not you can end up with some very serious discussion occurring from the 'lower end!'
The next step is to tip the platform sheet so it's flat, then wind the big wheel which moans and groans with the weight and then very carefully move the the 'lifter' in position, be careful, as at this point the whole thing is very unstable a wobbles at the slightest touch, once you get the sheet in the correct position you wind it into place.
Note: At this point you must have applied the adhesive to the ceiling battens or you will need to lower the sheet again, this may cause some 'light' discussion about the the 'work' demarcation and who's job is it anyway!
At this point you may be asking what happens if the contraption breaks and the sheet drops while you are winding, what we do is put the ladder and scaffold beneath the lifter, this will overcome the possible problem of the winding operator suddenly becoming a lot shorter
All things being equal you can then screw the sheet to the ceiling.
As the sheet is still a little floppy you need to be able to hold the sheet with one hand and then put a screw to the end of the drill/driver, a tricky little operation of moving screw which you have in the in the holding hand (done before the sheet holding) then carefully fit the screw in the drill fitting.
At this point it is a good idea to have a spare as sometimes the sharp little devils fall and you need to make some hasty adjustments. once you have at least 3 -4 screws in line the rest of the process is easy.
Repeat process until ceiling is covered.
For those into bits of useless information, we have 1.777tonnes of ceiling Gib now suspended above our heads.