Every Blogger will always be striving to make the most amount of money. Changing the colour of adverts, placement of adverts and type of adverts all contribute towards increasing CTR. However, no-one really mentions the shape of advert. Like all of above, vertical, horizontal and square shaped adverts all have different CTRs (click through rate): some will work better on your blog than others.
Horizontal adverts are mostly used in the header of the website all as links in 468X15 or the longer 728X15. Horizontal adverts are best used above the content or below. To incorporate horizontal adverts, try to make your blog posts length the same as the advert being 468 pixels wide. This will make the adverts blend into your blog's content. As I have said, 468X15/60 work great next to the header image of your blog. It will attract many views and as it is above the cress of your blog, anyone who visits your blog will see it.
These adverts have one area of placement: in your blog's sidebar. The adverts are so big such as 160X600 skyscraper that the CTR will always be fantastic on it. Just be aware that image adverts on adverts this big will effect the look and appeal of your blog. Try to also blend colours in with the same colours of your sidebar, contrasting is not good on vertical ads.
Rectangular 'Boxed' Adverts
These types of adverts are the most used adverts across the web. Why? Because they are so flexible where they can be put. They can be placed above or below a blog, in the sidebar and even in the content itself. People don't have to move their eyes up or down or left to right to read the adverts like they would have to do on the above adverts. It's all there, compacted into a box.
Ultimately, the decision of what advert is yours. However, my guild lines would be that:
- If you had a blog with a wide sidebar, use vertical adverts.
- If you have a blog with a small sidebar, use horizontal adverts above/below content and in header.
- If you have a blog with average size sidebar and blog post space, use boxed rectangular adverts.