Epdm roofing for a shed seems fairly thin at 1mm.
How to transition epdm to metal shed roof.
Trim off any large excess so that you have a sheet that s easier to deal with.
Thicker grades are used on industrial buildings as these areas can be subject to foot traffic over the years and so maybe 1 2 or 1 5mm thick.
Lay out one edge so that it overhangs by about 12 inches and then just pull the rest over the roof.
When you order epdm sheet it will be supplied in one large sheet.
Apply glue evenly and smoothly to the roof.