Have you tried practicing?
@overlay NAME rotates # anchor point x x in T
The symbols # x x and T NEED to be replaced. # and x x will be explained below (quote from the guide linked above). T is a number, the time, in seconds.
*# is a number between 0 through 360 (like the degrees of a circle)
- 360 turns the overlay all the way around, which turns it back to 0
- 180 makes the overlay upside down
- Rotating an overlay depends on it’s anchor point which is the point from which the overlay will rotate.
x x is the anchor point- anchor point 0 0 is the bottom left of the overlay
- anchor point 0.5 0.5 is the center of the overlay
- anchor point 1 1 is the top right of the overlay
To see where the anchor points are found, check out the guide I linked above, it shows a graph with the anchor points.
Ex.
&overlay NAME rotates 360 anchor point 0.5 0.5 in 2
I highly recommend to practice 
Also, you can have an overlay rotate 'round and 'round:
- To have an overlay rotate infinitely, you have to reset the the overlay back to 0
&overlay OVERLAYNAME rotates 360 anchor point 0.5 0.5 in [time] THEN overlay OVERLAYNAME rotates 0 anchor point 0.5 0.5 in 0 loop INFINITE times
So you can use the loop command with the rotation command. By the way, you can combine commands using AND/and or & (you can’t use and/AND in a looping command, you must use & when looping infinitely and don’t name your overlay with the word AND).
A tip: 🍭 TIP: Rotating An Overlay Without Having it Shift Somewhere else 💜