Login to your Adsense Account.
After you signed into Google Adsense, on top left side near home button you will be able to my ads, click on that and you will be able to screen like shown in the screenshot picture below.
The next step is to click on new ad unit and you will be able to see screen like shown in the screenshot picture given below.
To put Google Adsense ad in blogger side bar login to your blogger, and your will be able to see your blog name, click on that and you will be able to see screen like given below.
The next thing you have to do is click on layout, after you click on layout click on add a Gadget and you will be able to see screen like given below.
Click on save and ad will be displayed in blogger sidebar.
How to Adjust Sidebar Gadget or ad in Blogger
To adjust ad or gadget, just drag gadgets showing in layout page up or down, and automatically your gadget or ad will be shown up or down depending upon where you drag it.