This is updated follow this video.
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Step1:
Sign in your AdSense account.
Step2:
Click “AdSense Setup”.
Step5:
Now configure your ad size, text color, link color, background
color etc. you can see your change, left side as a sample.
Click continue.
Step1:
Sign in your AdSense account.
Step2:
Click “AdSense Setup”.
Step4:Now select “ad unit”, if you want image ad select from the right side.
You can also select “link unit”. But at first, select “ad unit.”
Now click “continue”.
You can also select “link unit”. But at first, select “ad unit.”
Now click “continue”.
Step5:
Now configure your ad size, text color, link color, background
color etc. you can see your change, left side as a sample.
Click continue.
Publish the code in your website later.