Start a new document 250 X 250 on a black background.
Select the Text tool option from the tool bar and to put some text on the blank document. I used yellow text because it stands out very nicely on a black background. Make sure that you make relatively large text, I used Gil Sans Ultra Bold font and set the text size to 34 pixels. That way it will be very easy to distinguish the rotating effect and be easily legible.
Click on the text on your document using the Selection tool and then click on modify on the toolbar, then animate, then animate selection:
At the Animate Selection dialog box set the following settings:
Once you click on OK it will animate your selection and you now have text that fades in and rotates three hundred degrees clockwise. If ask to extend the frames, answer yes. Play around with the settings a bit and you can come up with even more impressive animations.
Open the Optimizer Panel (Window>Optimize) and choose animated gif from the drop down menu.
Select the last frame in the Frame Panel (Window>Frames) and set it to 150 by double clicking on the number on the right side of the dialog box. This will drop down a menu where you will replace the default number 7.
Click back on Frame 1 then click the preview tab at the top of your canvas. Click the Play button to see your animation.
This is what your finished product should look like: