To increase earnings from your site or from adsense, you will need to increase the number of targeted visitors to your site. The best source are search engines. Try to improve your site's ranking in SEs so that traffic increase, which will increase the money you make from adsense.
This month I finally passed the $1/day mark in adsense (in fact I didn't just pass it, I blew it away, almost doubling my previous high month mark, and there's still a day left in October!) I wasn't even focusing on picking topics with high PPC, I was just writing whatever I felt like. But I was writing almost every day for much of the month. So I'm willing to hypothesize advertisers might be bidding more for a very actively updated site...
you must attract lots and lots of people. submit your site to many search engines, submit articles and attract the people from social networking sites, then definitely you can make some good clicks. if your visitors increases
Good Niche + Good content + Good Traffic + Good adsense placement in ur website {Merge ur ads color and text with your site } = Adsense Check
Another crucial piece of advice is to be persistant and patient. The fact is that you might not get Adsense right the first time round. What you have to then do is reasses your strategy and possibly start all over again. Some first time publishers are lucky enough to hit the jackpot the first time round. But this is rare. Many publishers get it very wrong in their first go, but what differentiates the succesful ones from the failures is their determination and their persistance. Take heed of all the advice you've been given in the posts so far and keep building annd learning. Before you know it you'll be making more than $5.00 a month. Good luck!