Make the book sum up. And then on the last page kill the most lovable character by the main protagonist and the protagonist likes it. How to make a characters death sadder
Great ideas! I do believe the physical appearance of the character is too important to leave out (I hate it when writers "leave it to the imagination." No, I want to definitively know what the character looks like!) But the "I woke up and looked in the mirror" trope gets old fast.
20 writing mistakes even native speakers make (infographic)
This infographic gives brief summaries of the 12 Jungian personality archetypes, for use when building charcaters. As with any writing tools, archetypes are really most useful if you think of them as a starying block - you cannot simply reduce people to 1