The best way to measure your correct size is to compare it to a similar garment you already own. Lay that garment flat and take all measurements from the outside.

 

All measurements in centimeter.

Size	Chest	Length
S	53 cm	69 cm
M	57 cm	73 cm
L	59 cm	76 cm
XL	62 cm	79 cm
2XL	64 cm	80 cm