Given my current position, I don't have a comparative advantage in reducing existential risk. So my strategy is (will be? akrasia...) to donate my time to the cause indirectly through money.

When it comes to my future day job, I'm pretty sure where to spend my marginal time: economic growth. Bringing growth to the non-western world brings more potential minds to work on the problems while increasing growth in general makes it cheaper, relatively speaking, not only to do the research that needs to be done, but also for people like me donate to the cause.

I suggest this basic plan for anyone who doesn't have a comparative advantage in working the problems involved in reducing existential risk: Go to your own field and do research that enables work on these problems. In economics, I am suggesting this is growth.

Also see rwallace's post - your babies can do the work you couldn't!