

1
The seams end on the shoulder. And you can place a finger between your neck and your collar. No more no less.

2
The shirt is adjusted at chest level. Little or no tension on the buttons.

3
There is no excess tissue in the armpits and back. Be careful, perfection does not exist!

4
Your sleeves stop at the level of the ulna (wrist bone).
HOW TO CHOOSE YOUR COLLAR WELL?
Nothing too complicated. FYI, there are 3 dominant passes:

ITALIAN COL
Often wide, it will be very flared to make room for a wide tie as well. A model that is perfectly suited to bureaucratic spheres. It is a very formal collar.

FRENCH COL
Recognizable by its opening of less than 90 °, it is straight, short and very versatile. This collar is compatible with wearing the costume, but you can also wear it as is.

AMERICAN COL
Buttoned, it is suitable for casual shirts. Avoid on formal occasions. And avoid choosing it too high or too pointed.
Other less frequent passes:
COL CUTAWAY
More flared than its Italian counterpart, it highlights the tie or the bow tie that you wear.
OFFICER COL
Often associated with the Mao collar, it wants to be relaxed and must remain naked of any accessory.
COL CLUB
It is the male equivalent of the Peter Pan collar: informal and dandy-inspired.
HOW TO CHOOSE YOUR MATERIAL WELL?
For formal shirts:

POPLIN
A very tight and silky fabric, see shiny. It is the most formal of all.

WIRE TO WIRE
More casual and airy than a poplin, it's a good compromise.

OXFORD
It is a fabric with grain, weaving often well ventilated. Perfect for all-season shirts.

CHAMBRAY
Much more relaxed, the chambray is woven with a colored thread and a white thread, for an interesting visual effect.

THE SHIRT OVER TIME
Over the centuries, the shirt has undergone many transformations.
Used as human underwear (and a means of social distinction) since Antiquity, it was transformed from the 16th century, to become at the end of the 19th century the iconic garment that we know.
Today democratized, it has many variations: on the wrists (musketeers, simple, bevelled), on the collar (French, English, American, button-down, Italian, cutaway, mao, officer), etc.