Recommended · for some experience
EEVblog #127 - PCB Design For Manufacture Tutorial - Part 1
Why people recommend it
First part of Dave Jones's PCB design for manufacture tutorial, full of practical tips such as solder mask pullback; usually recommended with part 2 for automated assembly.
Watch for: part 2 continues the tips
In their words
First of all, see these two videos by EEVBlog: Video 1, Video 2
Houen on electronics.stackexchange.com, Sept 2014. CC BY-SA.
Dave Jones recommends 1mm pullback I believe in his video here:
NickHalden on electronics.stackexchange.com, Sept 2012. CC BY-SA.
Excellent answers so far, I also recommend watching this video and part 2.
Matt Young on electronics.stackexchange.com, May 2014. CC BY-SA.