This helper allows you to mount your sandpaper perfectly aligned to your random orbital sander. 

I created 11 different jigs:

GLS 1
ø 150mm - 8 holes ø 10mm on hole circle ø 120mm
+ 1 centre hole ø 17mm*

GLS 2
ø 150mm - 8 holes ø 10mm on hole circle ø 65mm

GLS 3
ø 150mm - 6 holes ø 10mm on hole circle ø 80mm

GLS 4
ø 115mm - 8 holes ø 10mm on hole circle ø 65mm

GLS 5
ø 125mm - 8 holes ø 10mm on hole circle ø 65mm

GLS 15
Triangular ø 96mm - 6 holes ø 8mm on hole circle ø 52mm

GLS 27
ø 125mm - 8 holes ø 10mm on hole circle ø 90mm
+ 1 centre hole ø 10mm*

GLS 47
ø 150mm - 8 holes ø 9mm on hole circle ø 120mm
+ 6 holes ø 9mm on hole circle ø 80mm*
+ 1 centre hole ø 17mm*

GLS 51
ø 150mm - 8 holes ø 10mm on hole circle ø 120mm
+ 8 holes ø 8mm on hole circle ø 65mm*
+ 1 centre hole ø 10mm*

GLS 52
ø 225mm - 10 holes ø 12mm on hole circle ø 105mm

GLS 74
ø 150 mm - 8 Holes ø 9,5 mm on Hole circle ø 119 mm
+ 16 Holes ø 6 mm on Hole circle ø 119 mm*
+ 8 Holes ø 7 mm on Hole circle ø 95 mm*
+ 8 Holes ø 8,5 mm on Hole circles ø 65 mm*
+ 8 Holes ø 6 mm on Hole circles ø 39 mm*
+ 1 Centre hole ø 10 mm*

*) not printed, only the outer circle is used on my models.

You also might to see https://www.klingspor.de/en/lowdown-on-grinding/hole-patterns?set_language=en-de for reference which matches your sander, this is where I took the measurements from.

PLA with 0.2mm layer height will be fine, you can add a color change at 1.2mm.

The domes which hold the sanding paper in place are 0.7mm smaller than the hole diameter which makes handling easier but accurate enough.