It is very important to rightly place the Advertisement units in your WordPress blog in order to get the clicks. If there is no clicks, despite having thousands of visitors; you will not able to make any money, whether it is CPM based or PPC based Advertisement system.
The PHP codes of WordPress along with the experience of messing up the theme if the Advertisement codes (like that of Google Adsense, Chitika or Technorati media) make users think that WordPress is very difficult to place the Advertisement units.
Not at all. Yes, if you directly copy-paste the Advertisement codes of Google Adsense, Chitika or Technorati media, some themes got broken, but in majority of the cases the reason is the position of code ending (of the Theme) has not been chosen rightly.
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Today, we will selectively show the places where people usually put the Advertisement codes.
Sidebar
We guess there is no problem with sidebar. Still, for the starters, Just drag a new Text widget and paste the code you wish to show. Do not forget to save it.
Header
We will discuss case by case.
- Few theme has similar widgets like sidebar that allows to add the Advertisement units. Then it is very easy to add a text widget and paste the Adsense code (or other Advertisers code).
- You can manually add the Advertisement code after proper wrapping (read on) after end of the codes (code of the theme) in the header with ” >” in Theme editor and save it. Here is a screenshot:
Footer
Exactly the same for footer as we said about header.
Adding advertisement code in single page, single post, Home and tags and categories pages and comments
There is an excellent plugin named Post Layout that will do everything for you. Just install it and the option page will allow you to add where you want too add the Advertisement code. It will make your blog a money making machine for free. You can add anything, any HTML code anywhere you need with this plugin other than only injecting Adsense code. There is a pro version too those who want to fetch the best out of your blog.
Where is your Advertisement wrapping code for aligning to left or right?
Here is the wrapping code for your Advertisement unit, it will align the unit to right; if you need to align left, change the word right to left:
<div style="float:<span style="color: #ff0000;">right</span>;"><span style="color: #3366ff;">PASTE YOUR ADVERTISEMENT UNITS CODE HERE AND DELETE THIS LINE</span></div>
Adding advertisement code in single post along with a space with the text
Simply define a margin in the above code:
<div style="float:right; <span style="color: #ff0000;">Margin: 15px;</span>"><span style="color: #3366ff;">PASTE YOUR ADVERTISEMENT UNITS CODE HERE AND DELETE THIS LINE</span></div>
Increase or decrease the margin in pixel as per your need.
Adding two advertisement units anywhere side by side
Very easy. Just use one with align left and another with align right; like this:
<div style="float:left; Margin: 15px;"><span style="color: #3366ff;">PASTE YOUR ADVERTISEMENT UNITS CODE HERE AND DELETE THIS LINE</span></div><div style="float:right; Margin: 15px;"><span style="color: #3366ff;">PASTE YOUR ADVERTISEMENT UNITS CODE HERE AND DELETE THIS LINE</span></div>
This will place the two advertisement units to appear side by side. Do not forget the total width becomes: (width of two Advertisement units in pixels + 4 x margin in pixels). For example, with two 300 pixel width units and 15 pixel of margin it becomes (300 x 2 + 4 x 15) = (600 + 60 ) = 600 pixels width.
If your place can not afford it (say the place is 550 pixels width), one Ad unit will come down to the next line.

Oh wow, thank you so much for this. I have been asking all over the web how to get two 125 x 125 ads to sit side by side in my side bar. They sit one under the other. And I am not conversent enough with coding and such to understand what I did wrong.
Silly me finally remembered Google and found your website.
The rest of the information is also very helpful for me too. Your explanations are great and easy to understand.
Thank you again from a relative newbie to WordPress.
You are welcome Julianne. I am glad you got what you were searching for. Thanks to Google!
If you need any explanation or detailed tuts on WordPress, SEO, Windows or Mac; do not hesitate to ask me. In fact many tuts written in this website are based on the questions asked by the regular visitors!
Thank you very much Abhishek. I have also been searching the web for info on how to add a banner in my header and your simple instructions helped me do it. The other articles on the web are too difficult to understand and I wasted lots of time trying to understand them. Thanks again.
Thank you dejagib for your comment. I am glad that it has helped you.