By posting quality content (you could try practicing with your posts) that people want to read you will increase traffic, which will increase clicks. The more eyes you get to your site the better off you will be. It's all a numbers game.
Look at the google heat map: The more orange or red it gets, the more clicks it will recieve. Also post QUALITY content and try getting more visitors.
Yes,Build backlinks and do search engine optimization.These are ways by which traffic and clicks will increase.
To improve clicks, besides placement, play with the color and layout of the ad. You can change the background, border, text colors etc. all from the adsense control panel. Believe it or not but this can make a huge difference to the click through on the adsense ads.