Raise your arm and bend it slightly at the elbow (like you're looking at your watch). Using a tape measure, start at the centre of your back, just below your collar. Measure from here to the end of your shoulder and note down the measurement. Next, measure from the peak of your shoulder to your elbow, and finally, measure from your elbow to your wrist (where you want your cuff to sit). Add all three measurements together to calculate your sleeve length.
You can tell a proper button-down collar a mile off by its extra long points – just look at that elegant roll it forms. This one is made from sturdy cotton Oxford fabric (what else?), washed for softness.
Tyrwhitt loves the twill; so why not bring it to the weekend too? A soft wash, a relaxed collar, and an untuckable hem take it out of the office and ready to unwind. Still non-iron, of course – there are no jobs to do here.