You must show related ads on your blog to make more sales. I have just tweak my ads at my money blog. I have joined two affiliate products: stock product and forex product. So the right way to display these ads is to display in its related page. SO what I did was displaying the stock product in the stock category page, and show the forex product in the forex category page.
What I did was do some coding in the category.php file of current theme:
<?php if (is_category(’20’)) : ?>
— your ad code here
<?php endif; ?>
The code says that if current page is category 20, then display the ad. You can find out the ID of category by going to the “Manage Categories” page setting, where it will list all of your category for your blog. Hover your mouse above the “Category Name” you want to check, the status bar of your explorer will show the link to edit the category. The link will contain ‘cat_ID‘. This is your category ID.