Reely Nano Sky RtF Handbuch Seite 20

Sub Trim
The two buttons are elevator and aileron trimming. If there
is any deviation of the direction, the pilot can do trimming
by the two buttons.When hovering, there is deviaton in the
front, we can press the "elevator trim" button to make the
quadcopter fly stably; while if the deviation is in the opposite
position, press the trimming in the opposite position
accordingly. If the deviation is in the left, press the "aileron
trim" button to make the quadcopter fly stably; while if the
deviation is in the right position, press the trimming in the
left position accordingly.
for example
If the aircraft offsets to left when hovering, you can
adjust the aileron trim on the transmitter to the right
till the aircraft can hover in the air steadily.
Elevator Sub Trim
19
Aileron
Sub Trim