In the art of dressing up, just like in any other art, it is essential to have a grasp of the classics before one can venture into more kooky, individualistic style. An art student has to master the masters: their techniques, their thought processes, the rules they went by, before he can become his own man by building upon these techniques, or by simply breaking the rules altogether. Alan Flusser's "Style and the Man", now re-packaged and updated, is a compendium on matters of sartorialism that speaks to the everyman in a dignified, gentlemanly manner.
the new "Style and the Man" by Alan Flusser
It educates the reader on proportion, something that not too many have a keen sense of:
"Shoulders cut too narrow make the head appear larger than it is." An example of breaking the rules and moving forward: wear a jacket with shoulders too narrow to adopt fashion's recent fondness for a slightly smaller-bodied, bigger-headed juvenile silhouette.
and on shape:
"Straight point collars offset facial rotundity."
What I found most useful were the pointers on signs of quality in a garment:
for example, a horizontal buttonhole on the sleeve placket, or matching patterns on the yoke and sleeve of an expensive dress shirt.