you need good locations for your ads, and good choice of what ads you want to show. If you can get a good combination, your CTR should go up
Have you ever heard of these tags: <!-- google_ad_section_start() --> place summary of content here <!-- google_ad_section_end() --> with these tags you can fine tune the ads relevance. Try googling them, good luck
Try out some SEO themes. I edited a highly popular Blogger Template and created a new highly potent Blogger Template. This gives the flexibility of having a Skyscraper ad at a central position at your site. Check out the URL in my signature.
CTR is direct related to your content and ads format/placement. You shall try on different ads placement/format, monitor the CTR and found out the best. Besides, dont forget to improve on the content, it might helps
You need good traffic right.Promote your blog by searching it to blog directories,write good articles,advertise etc.