In the beginning, the shirt was not tailored, but more like a nightshirt. It was not until the 19th century that men were able to get shirts that were tailored to their bodies. In 1837, buttons were sewn on the entire front of the shirt, and in the 1930s, the collar was attached, and this has remained so ever since. A man's dress shirt should fit you well so that it flatters your body. You can know where to buy these shirts via this guide.
The body type and fit
Your body type will determine the fit of the dress shirt. The general fits of the shirt are athletic, regular or full. While athletic is the most tailored, the full shirt is the loosest.
The fabric and its pattern
When you are buying a man's dress shirt, you need to consider both the fabric and the pattern of the fabric. The fabric can be plain, striped or printed. Try to choose a pattern and a colour that will flatter you and your skin tone. Plain shirts, especially white shirts, can be considered formal, while stripped or patterned shirts can be more casual. The fabric itself is an important consideration. There are cotton, cotton blends, linen, Oxford, broadcloth, and twill. The fine cotton and Oxford cloth could be considered more formal. The linen, if it is very fine , could be formal as well. Twill shirts could be more casual. Poplin, due to being tightly-woven, could be a more expensive fabric to buy.
When you are buying a dress shirt, you need to consider other details as well, such as the collar style, the cuffs and the pocket (or not).
The collar can be buttoned down, tab, spread, pinned, rounded and
straight-point. Pick the one that would look best on you. The cuffs can be buttoned with one button, or if it is a French cuff, it will require a cuff-link for closure. Some cuffs can be either buttoned or closed with a
cuff-link. A chest pocket is common, but you can buy shirts that don't have them. If you are going to wear your shirt with a formal suit, then the lack of a chest pocket would be best, as it creates a nice smooth line.