If you plaster your site with ads, you implicitly hate your readers.
Please take this moment to reflect on what we really think of you.
Adsense does not a profitable blog make-- good writing does that. Readers respect good writers, and good writers are summarily compensated with readers.
Readers are money, so treat them that way. Invest in your readership and they'll increase in value. Spend your readership by delivering them ads or worthless dribble and you'll go broke. (Or worse, debt.)
Activity of the day: Calculate your blog rate of return (BRoR).
Take your adsense revenue and divide that by your blogging hours. If your BRoR is below $7, you're (much) better off waiting tables. Stop Blogging.