First Sign up here:
https://goo.gl/uB6ghySecond: You can choose to earn BTC or any other crypto.
Third: What I do is go to Earn Bitcoin at the top left, and then Watch Videos. Load up a video from EngageMe, a VideoLab, and let them run when you're asleep or not using the computer/s.
You can put the video on a different window and leave it running in the background.