the lecturer hands us these art blogs every now and then, and they’re really useful. Tangents are pretty easy to fall for, too! which sucks ‘cuz then it’d look weird and you’d have to re-do some stuffs or worse, re-do the composition of the whole image.
the rest & explanations in Chris Schweizer’s blog : http://curiousoldlibrary.blogspot.com.au/2011/10/schweizer-guide-to-spotting-tangents.html
John K’s blog is really good too (the guy who did Ren and Stimpy) : http://johnkstuff.blogspot.com.au/2006/06/animation-school-7-when-generic-is.html