you must log in to your blogger account, and then click to Dashboard, then you will see your layout and click in it. you can put ads with many layout from your template. Click to add gadget and choose Adsense label.. and finish your work. see my blog under as an example to put adsense in blogger blogspot. best regard for you.
To put ads on blogger---IT is the simplest way to put adsense on blogger. GO TO DASHBOARD>>LAYOUT(OR SETTING)>> CLICK MONETIZE TAB and follow instruction there. Once you have activated your Adsense account, you can log in into google.com/adsense/ and you can create more adsense code and use them in blogger by adding those code in Java.html gadget .... How to increase Traffic >> Keep reading post in DP (search engine optimization) and you will get a lots of idea and tips.