Occasionally I get reminded about an older article. In this case, it was prompted by an email from the publishing website. But this is a very good article about complexes.
Rebuild Yourself with Complexes by Dan John.
It's a fairly quick read, and it's got the usual sage advice of Dan John. Such as "...many of the exercises will be fairly familiar to all of you. If you don't know how to do a lift, don't do it."