How to offer peer review comments

I was recently asked by an editor to offer (single-blind) peer review comments for some upcoming academic work on the Singularity. Having never done this before, I sought out some literature on how to do it.

In case others find themselves in this position, here are some helpful papers I found:

But I know that many Less Wrongers have been engaged in the peer review process for many years. If so, please offer your own comments or link to other helpful instructions!