How to adjust Avid Elixir 1 hydraulic disc brakes? I have a Trek X-Caliber and the rear disc is rubbing a little. So I want to adjust the brakes so it doesn't rub and make things a bit easier of course.

I see many videos about brake adjustment but none for this model (Avid Elixir 1) and I am very worried about playing around with the system and then end up making things worse...or with no rear brakes at all.

I live in thailand and there isnt a good bike shop where i live.
The manual says they are self-adjusting but a shop told me you can adjust them slightly by loosening the rear caliper from the frame, squeezing the brake pedal gently, and tightening the caliper back down to the frame (to specs of course). Also, be sure not to loosen the screws holding the two sides of the caliper together, otherwise you'll let the fluid out and air in.