[sophacles]

I'd add:

Unless you have a good reason to say "No" [1] to stuff, say "Yes". Doubly so in outside of a "work task" context[2]. More experiences/involvements means more opportunities for fortune to look your way.

[1] Good reasons to say "No" - already committed, the ask will hurt you, I need rest, i can't afford that. Bad reasons - this is odd/out of my comfort zone/not interesting, it violates a routine, "I'm waiting for..."

[2] I really really mean "outside of work tasks" because just saying yes to every little request at work can result in work overload and the inability to do life. The point of work is to enable life, not to spend the entirety of it staring at $IDE.