not the "boot effect!" As a general rule of thumb, socks should match the color of your pants, not your shoes (or it creates a weird boot effect). Of course, if you want to wear statement socks, then by all means so long as they are tasteful.
Men's long sleeve, plaid, button up, flannel shirt. No rules on how to wear it. We go for casual style so we outfit it with jeans and boots. But your shirt, your call. Great gifts for guys dads men who have everything.