Getting the perfect fit is always important, here’s how to measure!
Lay one of your own T-shirts (or whatever type of garment you’re comparing to) on a flat surface and smooth it out.
Measure the WIDTH across the chest from about 2.5cm below the armhole (from side seam to side seam).
Match this figure to the nearest size on the relevant size chart for that garment.
If you’re unsure, order one size larger!