Here's how you do this easy trick.
Get the code
1. First go to PrintFriendly website : https://www.printfriendly.com/button
Chose your custom button.
2. Go to the bottom of page and Copy-and-paste the code into your HTML where you would like the PrintFriendly & PDF button to appear.
In blogger
Step3: Paste the code (PrintFriendly website) into your HTML where you would like the PrintFriendly & PDF button to appear.
It look like this: