effects

This is a mode thing more than an Effect thing.

If you press the Gobo encoder down you'll get to the "modes" for the Gobo wheel.  There should be at least one that says rotate.

Then another wheel should control the spin speed.

I find the ML control display easier for many beginners. All the options, buttons and settings are in one place. It's slower and you need to see screen and stage at the same time, but easier to understand.

Select one or more fixtures then Displays> soft-key "ML Controls"

As Patric said it's not an effect. Gobo rotation is a function of the light so it has it's own control in the channel. You might use an effect to have the fixture change the gobo every so often, or speed up/down the rotation in a pattern.

I find the ML control display easier for many beginners. All the options, buttons and settings are in one place. It's slower and you need to see screen and stage at the same time, but easier to understand.

Select one or more fixtures then Displays> soft-key "ML Controls"

As Patric said it's not an effect. Gobo rotation is a function of the light so it has it's own control in the channel. You might use an effect to have the fixture change the gobo every so often, or speed up/down the rotation in a pattern.