How to wear a Paul Smith or Etro shirt?

The green shirt isn't really wearable.

The first shirt would go well with non-baggy black pants. Probably with black belt and shoes that are moderately dressy.

The third shirt could be worn with a wide variety of clothing, though likely best with jeans.

Any of them could go with jeans and something like an unstructured khaki blazer. Also, cream or gray linen pants, and again, an unstructured blazer.

You have to go for a certain playboy in Monaco type vibe with those, they're really not good for anything else. Maybe under a sweater in winter, no tie, like you might wear a bold plaid sport shirt.

Shoes? Loafers. With colorful socks. Maybe a boat shoe or camp moc.

I have a Paul Smith shirt that is very similar to the first one. I wear it all the time. I also like the second one, and would have no issues fitting that into my style. The third is not my cup of tea though.

This was from a week or two ago: http://wisith.tumblr.com/post/25910294346/sun-was-in-my-eyes

I loved these S/S 2010 shirts but never saw them for sale.

I would probably have only worn it once by now, though, so I'm not losing any sleep over it.

As for how to style them, the runway show pics ought to be good for some ideas, though they will give GBR and the rest of the dried-up MC grandparents well-deserved seizures.
Etro ss10 (Click to show)
Long story short, jeans aren't the only option, and they may in fact be an easy way to go astray.

GQ has a slideshow and fullscreen option of the whole show

The third shirt can look really nice with cream, white trousers, or dark jeans.

I have a vintage floral Charvet shirt in navy, chocolate, tan, white and gray that is similarly busy. The difference being that it has a straight hem and small hip pockets similar to a long-sleeved guayabera.

I wear it -- on the occasions that it is appropriate -- with linen or tropical wool trousers and either an easy loafer or nicer sandals.

A linen jacket will work but make sure to use a contrasting jacket.colour such as Cream, Navy or Choco Brown.

Pick up one of the shirt colors in a solid colored sock for fun.

Sure these are shirts and not pyjama tops?