A month or two back Google seems to have moved most of the indexed pages on My site to its supplemental index, which I figured out recently. I need some help in getting the pages moved back into Google’s main index.

My site is a blog that has been set up for three reasons
1. As a possible reference for other developers and tech guys in general
2. As an online repository (or notes) for my own reference
3. Play ground for learning SEO, though it is not my profession or area of expertise (but i'd like my blog to be positioned high on Google)

and revenue generation is not the primary objective.

Can anyone give me some good tips on how to effectively move the indexed pages back to the main index please?