First of all sign in to your G Mail Account
This will only work in Google crome
Step1. Goto Google chrome store By Click here
Step2. Type in search option "ads blocker" and click enter
Step 3. Choose ad block plus from the result and click add to chrome
Step 4. Now click add
This will take about 10 sec for 512 kbps speed internet
or 1 min for 64 kbps internet
Browse you tube video free of ads
See address bar for this icon for verify that this software working properly