I am sharing a method that I have been using to make $1000+ per month from my 5 -7 websites only with Adsense.
I used very simple techniques. I used only the free tool "Google Insights for Search" to identify the keyword
1. I analyzed some potential keywords on google insights and checked their treads. And for the keywords which gets more than 200 -300 searches per day, I checked for the availability of the exact match domain for that key word (.com or .net or .org) and at the end of the day I bought seven domains. Two were .com There were .net and Two were .org
I did not want to register anything other than .com .net .org
On google insights, I always compare new key words with a key word for which I know (or I could calculate) the monthly/daily searches roughly. So, I can get a rough idea of the number of searches of the other key word too. Google trends also can be used in the similar way
--Completed this step in 5-6 hours
2. Set up auto blog (wordpress) tor all seven domains
--Completed in 1 hour
3. Then I started working on bringing those domains to the #1 or #2 or #3 or etc on google
Built some backlinks using some simple, less time consuming methods, such as Profile backlinking & blog comments.
Spent around $100 - $150 to do SEO during the first month (to outsource the backlinking work).
--Total time spent for this is nothing for me as I just outsourced the work.
Since I don't want to spend my time on link building, I use automated solutions / out sourcing the work. But, If you have plenty of time you can do the link building yourself too, that will make this cost $0 but cost time. It all depends on your Time/Money Ratio....
After 5-6 weeks my websites started getting 600 - 800 daily visitors (Total from all the above websites) and my daily income was $10 - $15. And after the second month onwards it started giving a $30 /day.
During the first and second months four of those websites encountered the "Google Dance" too. However it was not a problem as it was temporary (lasted for 2-3 weeks).
Now I don't do any manual link building as all these website have passed the google dance. Not spending more than $100/month (& not spending any time too) for the income of $1000/month
You may use any backlinking methods depending the availability of resources
What is the advantage of this method?
It is highly competitive to get top ranks for the highly paying keyword as all people are doing key word researches every day and trying to get top ranking for highly paying keywords.
Since, I concentrated only on the number of visits I had a very small competition (because most of the people try to get ranked for the highly paying keywords and my keywords are not the highly paid ones) and was able to bring the websites to the top positions without much difficulties.
Though the average PPC was around 0.1 -0.6, with 80 - 120 clicks the daily income is $30 - $40
CTR - 8-10%
CPC - $0.1 - $0.6
I use ProSense WordPress theme, it's free.
Any auto-blog plug-in or conf will do as the onpage SEO doesn't matter much, as long as the basics are followed.
So, the monthly income by adsense alone is $1000+ (Note : Without spending time)
It is a very basic work without any advanced tools or concepts. After some fine-tuning the income can be improved even more!!!! I just started it as a testing method so still I see there are many things to be improved in order to increase the income.