From the menus, choose Composition > New Composition.  Name it Text and click OK.

Right click in the Timeline Panel, and choose New > Text

Choose a font and size from the Character Panel.  Click in the Composition panel and type your text.

Now click on the Effects and Presets Panel.  Type fractal noise in the search box.

Click and drag the fractal noise effect and drop it onto your text in the composition panel.

Now, look over on the left in the Effect Controls Panel.  Choose an animation preset that you like the look of.  I chose Cosmic Power.

Press Space Bar to see your effect in the composition panel.  It doesn't look very exciting yet, but we will fix that by adding the Colorama Effect.

Type Colorama in the Effects & presets search box.  Click on the effect and drag it onto your text in the composition panel.

Expand the Output Cycle by clicking on the little arrow on the left. Go to the preset palette and choose an effect from the drop down list.  I chose Fire.

You can see what your effect looks like by pressing the SpaceBar, or dragging the yellow timeline indicator.

Experiment with the other settings in the Colorama and Fractal Noise effects to see how they change.