Know the Fitting of your Clothes

The Right Fit
How jackets and trousers should break, fall, sit, fit, and look their best.

The Trouser Bottom
Only a little cloth should ever drape on your shoes; ask your tailor for a one-inch break in your front crease.

The Shoulder
No outline of your own shoulder should appear in the sleeve, and the sleeve's head should never sag.

The Buttons
There should be no creases or ripples radiating from the single fastened button. If there are, switch up a size (or, even better, lose some weight).

The Shirt Cuff
A quarter to a half an inch of shirt cuff should always be visible. Maintaining this is one of life's greatest challenges.

The Collar
The collar of your jacket should not stand away from or conceal your shirt collar.

The Jacket Length
The bottom hem should be level with your knuckles. (Or, alternatively, it should be just long enough to cover your ass.)

Source: MSN