I do not dress up even when I go out, so it should come as no surprise that this is how I dress up (or down, if you must) when I’m at home. Just a baggy (but clean) t-shirt and comfy shorts. And rubber flip-flops of course. The name of the game is comfort, plain and simple.
Nothing beats the comfort of all PE t-shirts. Old, as in elementary-and-high-school-days old. You know, those that are already worn smooth and already yellowish from all the years of use and abuse but still managed to survive intact. It may sound gross and all, but for me it’s not. The older the (baggy) t-shirt, the better.
Same applies to friends, in most cases.