Dark jeans + black/grey/white Tshirt and 30 minutes a day in the gym is a fine start. Then a white dress shirt. Then a grey suit with the white dress shirt. Then a navy sports coat. Whatever you do, buy good stuff and keep it clean. No Ed hardy, Robert graham or logoed shirts. Take the time, make the right choices on the basics and stay near there.
Provided you get the right size, you can't go wrong with the fit of Alden/Allen Edmonds. If you get the wrong size, they are a terrible choice. They just seem to be a much stiffer shoe, so take the time to try on the various lasts and widths. The shoes will last 3x longer than your JandMs. The GuccisFerragamas would be a good shoe as well.
A grey sweater is perfect. + a light blue.
Just get a navy sports coat and then a grey suit. You can wear the sports coat with chinos, dark jeans, grey slacks. Mix in the sweaters and 5 dress shirts and suddenly you've got a bunch of combinations.
If you are an art student, you only need one suit. Nothing too fine.
He is absolutely correct on tan stuff. That's a whole different lesson for a year or so from now.
Shoes--A wingtip would be perfect--Allen Edmond Strand too. Go to Boston, get sized at a store, then order from Shoebank.com
The black/white sports coat is a terrible idea.
Youre off to a great start Id say. dont shy away from jeans, but get a nice, dark denim pair--trim or classic fit. Not relaxed, baggy.
For your shoes, get a pair of brown shoes for the other pair. Khaki chinos are as universal as people think, and dont go well wih all colors, but grey can be pretty slick.