1. Shoulder pads end with your shoulders.
2. Your flat hand should slip easily into your suit under the lapels when the top (or middle) button is fastened. If you put a fist in, the suit should pull at the button.
3. The top button of a two-button suit — or the middle button of a three-button suit — should not fall below your navel.
4. With your arms at your sides, your knuckles should be even with the bottom of your jacket.
5. Jacket sleeves should fall where the base of your thumb meets your wrist.
6. Between a quarter and a half inch of shirt cuff should be visible.
7. One inch of break.
I found this to be very helpful for men who rarely wear suits or have that special suit they wore 5 years ago. Sometimes you can take a suit to a tailor to re-fit the pants if you need to let out the waist. If you decide to go to a tailor to alter a suit for a special occasion, do it a month before the event. My husband took a suit in to a tailor and they wrecked the pant. They cut the zipper area re-adjusted it and it did not fit correctly. Should this happen to you, you will have enough time to shop for another suit and have it tailored in time.
Spring is the time for weddings, graduations and communions and more often than not, You will be wearing a suit. I haven't found a great men's tailor and am looking for one still.