Ask HN: Should I trademark the name of my startup?

I kept wondering if trademarking the name/logo of my startup is worth it.

* If so, when is the best time to do it, before or after launch?

* Should I hire a lawyer to do it, or is it simple enough that even I can do it? (I'm a software engineer with no legal background)

* What are some of the caveats of the trademark process?

Thanks!