The BLUE mode on the shifter indicates Automatic operation, while the ORANGE mode is Manual mode, which shifts just like a regular bicycle. You can switch between BLUE and ORANGE using the silver button.
When you’re in Orange mode, rotating the shifter AWAY from you makes it EASIER to pedal - rotating it TOWARDS you makes it HARDER to pedal.
When in the Blue mode, we recommend leaving the shifter in the ½ way position, which will provide a smooth and easy ride.
Take a look at the blog post linked below that highlights this in a bit more detail: https://www.evelo.com/blog/continuously-variable-transmission-cvt-on-evelo-electric-bikes/