For some, it takes some time to get the hang of it; just be patient and try to relax. Also, make sure your phone brightness is set to maximum and that you are in a somewhat darkened environment. The EyeQue logo on the miniscope must be facing the bottom of your smartphone.
The last tip that we can give you is to move the the miniscope's eye cup so that it touches the bridge of your nose. Depending on which eye you are testing, slowly move the miniscope to the right (right eye) or left (left eye) until both lines are clearly visible. When the two lines are visible, try to maintain the position of miniscope as you ensure the eyecup completely covers your testing eye. This should give you the clearest view of the two lines within the miniscope.