1: go to chrome://extensions/
2: in the top right turn on developer mode.
-------> 
1: download this somewhere on you're PC. (Do not move or delete this afterwards, or you will need to follow this again)
2: open chrome://extensions/
3: have developer mode enabled in chrome 
4: click the newly found button Load unpacked 
5: browse to where you have you're extension downloaded and hit open
6: you're good to go!