American Fashion designer, Thom Browne, releases his 10 step rules for properly wearing a suit.  See below.

#1: “Only the middle button on the jacket should be buttoned when you are wearing it closed.”
#2: “The pocket square in the breast pocket should be just peeking out (no more than 1/8 of an inch).”
#3: “The last button on the cuff of the jacket should be left unbuttoned.”
#4: “The button-down collar of the white oxford shirt should remain unbuttoned.”
#5: “Please do not iron the oxford shirts after washing.”
#6: “The trousers should be worn high-waisted so that the cuff of the trouser falls above the ankle.”
#7: “The neckties have been pretied, but please remember to keep the knot very tight when tying the necktie.”
#8: “The necktie should be worn long, with the tip of the tie tucked into the waist of the trousers.”
#9: “The tie bar should be clipped so that it falls halfway between the collar of your shirt and the waistband of the trousers.”
#10: “The shoes should be worn without socks.”

via WhiteliesMag