Many people rush behind Adsense optimization.They see google official videos,they read blogger tips like Change colors,Use larger formats,put more than one unit.
After doing this much also CTR doesn’t go high.May be change of 0.01%,which is negligible.So what was the matter ?
Your daily unique visitors.Before you do adsense optimization you should make your content rich , good alexa i.e. high daily unique visitors ~3000-4000.
Why I am writing this ? because if you getting 200-300 visitors a day and not seeing change after optimization that’s obvious.Out of 200-300 visitors you can’t decide which ads,colors are great for your site.More over out of them many of have tendency to not to click ads.They don’t see at ads.So ultimately even though the ads format colors were perfect for your site the result is failure.
So better first build good visitors then do changes in site as per adsense matters.This will give you perfect result of optimization.