Wings Aimation

Hi everyone!
I have a logo of a fairy, and I'd like to move her wings to front and back in Y Rotation,
but I need the movement to be repeated and doing it manually with the Record button will take forever.

Do you know any different method? Please help
ps. i have LEFT part of the wings and RIGHT one separately

Two ways:

1- Keyframe the motion once. Then look at the keyframes int he Keyframe Editor. Lasso those in, right-click, set them to "repeat" after they finish.

2- Assign the Rotation Y parameter a "Rate" parameter behavior.

Another approach:
Move the anchor point to the point where the wing is attached to the body.
Open the Rotation properties of the wing shape in the Inspector.
Twirl open the small triangle from the Rotation parameters.
Right-click on the Y rotation and add the Parameter Behavior "Oscillate"
Tweak the settings to your liking.

Mark Spencer did a tutorial at Pixel Corps (Ep. 165) that sort of discussed this. Check it out on their YouTube channel.