Help With Keywords

creating a blogger blog (first real go at making money from adwords) if i can make even a little bit of money off it, I'll invest in domain and hosting and do it properly!

just a few quick questions for you bunch I love this forum been browsing it for a few months now everyones really friendly and helpful, taking action today!

how many keywords should I use (to start with)

how how many (exact) searches should my main keyword have atleast?
and how many searches should my others have?

don't want 'spoonfeeding' I'd just like some general advice

any other blogging advice would be much appreciated

I could right a book on this, how many pages is your blog going to have?