Say yes to that which will bring you further and say no to that which holds you back.
What are your personal areas for improvement? Say yes to anything you possibly can which falls in this umbrella. Do some risk-reward comparison – i.e. you might say yes to a meetup but not to a six-month long seminar series.
Self-interest only goes so far. Once your life jacket is on, consider how you can say yes to things that will make your coworkers’ lives better or strengthen your community.
Say no to preserve yourself. Preserve your time; preserve your dignity.
If your time or your mental bandwidth is currently limited, say no but with regrets. Be clear that you’d love to be approached about similar stuff in the future. If you can, specify a time frame.
If you’ve been a coworker’s personal Google or you’ve stepped in to keep the ship from sinking, often you are expected to keep on doing it. Don’t let someone else’s responsibility become yours without your explicit consent. Saying no here can be intricate; it could involve helping to make a plan for your coworker to have access to better documentation, or creating that documentation yourself. Saying no may be more work than saying yes. It’s still the right thing to do.
If you are being asked to do something far above your skill set, but you want to say yes, clarify expectations first. Is there support for you to learn as you go? What are the consequences for failing? Why are you the one being asked?
When you are being asked to do something below your skill set, consider it carefully. Again, why are you the one being asked? Is there currently no one else available? Is it because it is easier to ask you? Or because they know you will do it quickly and accurately?
Make consequences clear before accepting. If you say yes, something else that is in your skill set may not get done. If you will do it only once, say so and mean it. If you will do it on the condition that you help figure out a way that you won’t be asked again, offer that.