Adsense CTR relates to Ads

Adsense CTR obviously increase if you make sure the ads that are appearing on your blog or website are closely related with your content. If your ads are not relevant, people hardly click on them. If you have a blog about video games that has ads for video games you have a higher chance of a click than if your video games blog has ads for dog food on it. In most cases, the more relevant ads are to the topic of your content - the more likely you are to get clicks on your adsense ads and increasing

Ads Format: Wider ads appeal to more visitors because they're easier to read. If something is easy to read, someone is more likely to take the time to read everything rather than just glancing at the first few words. For high adsense CTR you should find the place and format that works best on each page. Following are some tips for you.
# Use Text Ads, not Image Ads.
# The most effective ads is the rectangle box and vertical large banners. Avoid horizontal ads; users already got used to ignore them.
# Gooooogle states that the most effective ads formats are 336×280 larger rectangle, the 300×250 medium rectangle, and the 160×600 wide skyscraper. You may get high CTR.
# A number of the high-trafficked blogs, add a double block of 336x380 "Large Rectangle" blocks at the very end of a Post or Webpage, when a visitor is about to leave.

Ads Colour: You can create a custom AdSense colour that best suites for your AdSense blog or website. To get high CTR, you can follow the following settings:
Text colour : black or colour of your main content
Border color : no border or background color of your blog or website

Background color : Matching your website colors

Link color : color of your links

URL color : black