Originally Posted by
Fuuma 
Wearing sneakers with a suit can be a good look, but you have to follow the precepts to
Fuuma's guide to everything, ever (now on sale for four easy payments of $67.99, buy now!):
-The suit has to be from a brand SW&D likes not something MCers wear: Dior Homme, Raf Simons, Helmut Lang, etc.
-You need to wear simple white sneakers (think white/white stan smiths or delicate designer sneakers (think Lanvin), avoid all sort of trainers/running shoes/shiny Nike shit
-The rest of the outfit has to be casual, no tie, no patterned suit, material of the suit is cotton, moleskine, velvet, shiny wool etc, suit is slim and maybe shorter than usual. Maybe you wear a v-neck tee instead of a shirt, if you wear a shirt it absolutely has to be white and plain and not have silly stuff like a spread collar.
-You need to have a look (facial hair, haircut etc) that labels you as some casual dude, not some office dude.
-If you are Italian or a blogger just give up, you don't have what it takes for this look.
The reason the Pitti-spazzatura-GQ crowd dresses like shit is made painfully obvious by the way they use sneakers: they think one casual element is enough to bring a fun casual touch when it reality it is how you start from a casual mindset and mix various casual elements. They're the fun socks of dressing....