So, we're a heavy man and carrying a little extra around the midsection. Not to worry; we've got you covered!
This article will give you some style, tips, and inspiration on how to dress as a heavier gent.

Fit is paramount for any body type. We'd suggest minimizing the amount extra fabric you have, as it adds bulk to your frame.
If you're particularly pear-shaped, you may consider going custom, especially with your suits. This is especially true if your waist and hips are larger than your shoulders, as you'll likely have to size up.
This can result in an extended shoulder pad and sleevehead, which leads to unsightly divots around the shoulder area.
If buying off-the-rack, consider suits in portly (two-inch drop) or stout (no drop at all) sizing.

Suit Style As A Heavy Man
You can consider a three-button jacket as a heavy man, as it will add some height and elongate your figure.
A two-button works just as well, though, particularly if that jacket has a higher button stance.
Seek out jackets that have a slightly higher button stance, as they conceal more of the midsection.

Look for a slightly structured shoulder. That extra width balances your waist and hips, making you much more proportional.
You'll want a balanced lapel that isn't excessively wide or (especially) narrow. Notched lapels are probably best here.
Center vents can work on a jacket, but will jut out awkwardly in the back if your torso is too tight. That's also the case with a double, English-style vent.
If you're particularly large in the seat, we'd suggest adding a strap to the back. That keeps the vent from jutting out.
Jetted pockets add to the vertical look. We'd also suggest a double-welted pocket. While more formal, the lack of a flap means even less bulk and a more streamlined fit.

We advocate medium or lightweight fabric, especially if you tend to run hot. Open weaves, hopsack, and even tropical wools can be fantastic. We'd suggest avoiding particularly heavy or fabrics like tweed.

Patterns and Colors:
Vertical stripes are very much going to be your friends. We'd suggest pin and pen stripes on suiting. Small patterns are okay, but we'd recommend avoiding chalk stripes or particularly large windowpane checks.
As for colors, darker and muted tones are also going to be best for you. More importantly, dark blues and charcoal tend to command power and authority.
So, we'd suggest navy suits, charcoal suits, and the all-important uniform of a navy blazer and charcoal trousers. And, we'd suggest keeping them closer together in shade, as too much contrast breaks up the vertical line we'd like so much to keep.

Shirts, Ties, and Trousers for A Heavy Man:

Shirts and Ties
Regular point collars with a slight to medium spread are going to be the best for you. We'd suggest avoiding tab, pin, cutaway or extreme spreads, or club collars.
As for shirting styles, small patterns are fine. We suggest vertical stripes (just make sure they're of a different width than your suit stripes) to elongate and slim the figure. We recommend avoiding larger patterns or horizontal stripes.
Do be mindful of bow ties in many cases, especially if you've a double chin. Additionally, subtle ties will be best here, as they will with most figures.
The collars to avoid are spread, tab or pin and club (round) collars. Regular point collars are best. No bow ties please, especially if you've got a double chin. Go easy on tie patterns. Make sure the tie hits your belt buckle to avoid that horizontal gap. Even in casual wear, long sleeves help with proportion and will look better.

Wear your pants on your natural waist (in line with your belly button). Wearing your pants under the belly just highlights it.
Pants with either a single or double pleat are going to be very flattering as well.
We'd also suggest trousers with a 1.5inch cuff. The extra fabric adds weight and helps the cloth to drape nicely, creating those vertical lines. Pleated pants which are a style must for everyone else are a requirement for you.

Shoes and Accessories for A Heavy Man

We'd suggest going for thin-soled shoes with a little extra material as possible. Look for Oxford-style shoes in streamlined lasts with a thin sole.
Consider darker shoes in general as opposed to lighter ones. Avoid heavy-looking shoes, also anything light colored with thick soles. Try dark shoes with thin soles.

Vests can work well if they're part of a three-piece suit and have a higher buttoning position. Contrasting waistcoats are meant to stand out, which just draws attention to your middle.
Additionally, we'd suggest going with pocket squares to add some flair. They're small items and sit higher on the chest, which draws attention to that part of you instead of your waist. Interesting socks are a great piece as well!
If wearing a belt (note: belts should not be worn if you're wearing a waistcoat!), consider a thinner belt with smaller buckle. Larger belts, "cowboy" belt buckles, and the like will draw attention to your midsection.
Eyewear Shape:
Look for styles with vertical lines such as high temples and a high nose bridge. Try glasses with wide frames to span your face. Rimless glasses add length to your face. Large or wide noses look best with low bridges in clear or metal (no dark colors, please).
Single-breasted with a set-in sleeve is best.

Summing Up
So, as a heavy man, we'd suggest going for muted, but rakish and refined, tones in your suiting. Favor solids and vertical stripes over checks and windowpanes.
Accessorize with pocket squares and perhaps a bright pair of socks.
Go for sleek shoes on refined lasts instead of the omipresent square-toed slip-on shoes.
And, as always, confidence is key. Here at Ask Andy, we believe gentlemen of any size can have fabulous style. John Wayne and Cary Grant didn't have six-pack abs and they still looked darn good in their clothing.
You can too. Thanks for reading, and we hope this piece helps you toward dressing better as a heavy man.