The best way to measure your correct size is to compare it to a similar garment you already own.
All measurements in centimeter.

Size	Chest	Length	Sleeve
S	30 cm	38 cm	11 cm
M	33 cm	41 cm	12 cm
L	34 cm	43 cm	12 cm
XL	37 cm	44 cm	13 cm
2XL	38 cm	46 cm	14 cm