Are there any self-improvement guides that are strictly from Islamic sources?
Especially ones that are based on the Quran and Ahadith. It should be the way to go, since Allah did say in the Quran :
>And whoever desires other than Islam as their Deen (way of life) - never will it be accepted from him, and he, in the Hereafter, will be among the losers. [3:85]