Have your pants hemmed so they break properly over your shoes.
I don’t know what can be done about sleeves that are too long when you have a large neck and girth- but it’s bad.
Don’t wear a button down collar with a suit.
Dress shoes should be polished and a current style.
If you are on the heavy side, avoid loafers- even if you’re not, oxfords are better.
Navy is always better than brown.
Plaid, Madras or Seersucker for short sleeve shirts- no solids. A t shirt ( only wear graphic tees if you have seen the band, drank at the bar, etc.)is usually better than a Hawaiian shirt, if Hawaiian, choose a reverse print Reyn Spooner pullover style.