I always wear cycling overtrousers which keep them perfect
for the top half, best tips I have are
-buy cheap shirts. The more expensive, quality cottonn ones will look a mess compared to a 10 quid primark one ! (I have a wardrobe with loads of quality shirts I rarely wear now). Sounds daft I know but the end result is not looking like a scruff bag!
-don't wear a backpack. Get a rack/panniers
-let the bike do all the work on the way in on max. Do your excercise on way home !
-keep a spare shirt at work for emergencies
- go "shirt sleeve order" ie folded up cuffs (hides badly cruplmed sleeves)
- in winter wear a fleece under your cycling outer (9 years cycle commuting experience and this prevents the creases dropping out of shirts - don't know why but it does )
- Finally we have fixed hairdryer on the shower cubicle walls at work. In waterproof failure emergencies I have dried trousers this way ! Eventually ....