I read some reviews of this shirt about the sizing which stated buy a size smaller that you would normally buy, so I bought a medium as I would normally buy a large.  The medium was too small.  I returned and bought a large which is perfect.  So for me, I buy this shirt in a large as I would for any other shirt I would buy.  The shirt is wrinkled when arriving.  I used a steamer, and it removed the wrinkles nicely and quickly.  Be careful using a steamer.  It is nylon/polyester, so I just hit it quickly and don't leave it too long in one place.  The steamer is always moving over the fabric.  Good shirt. I like it , and will probably build a collection of these in different colors.  Excellent summer shirt, and will be cooler than a T-shirt in my estimation.  Never heard of a fishing shirt before.  Glad to make this discovery, though I will still get my fish from Costco and wear this shirt as I buy them.