We want our particles to fade out as they die, which will have the effect of smoothing our animation. We'll use the gradient in the Opacity Over Life parameter to define that fade.

Set the cell fade over life

1. In the Layers List, select the particle emitter object.
2. In the Inspector, select the 'Emitter' tab and view the Cell Controls section.
3. In the Opacity Over life gradient editor, set the location of the default tag to 30%.

4. Click anywhere inside of the gradient band (now a white bar) to add another tag.
5. Drag the new tag to the far right (Location = 100%) and set its Opacity to 0%.

By looking at the gradient, you can see that each particle will stay opaque until 30% of the way through its lifespan, and then it will slowly fade out.

Our last tweak will be to add a little randomness to the lifespan of the particles by applying a behavior to the Life parameter. The Randomize behavior would be too harsh, so we'll use Wriggle.

Apply the parameter behavior

1. In the Layers List, select the particle emitter object.
2. In the Inspector, select the 'Emitter' tab and view the Cell Controls section.
3. Right-click (or Ctrl-click) on the Life parameter's name and choose 'Wriggle' from the menu.
4. If not already there, select the 'Behaviors' tab and view the Wriggle parameters.
5. Set the Amount to 1 and the Frequency to 2.

Now you have a delightful sandbox in which to explore all sorts of changes. Try changing the font of the source text:

Or how about applying a sequence behavior to the text:

Or maybe trying a couple of different filters on the parent group:

Hopefully, this tutorial has given you an idea of the potential for particles to be used in type treatments. Experiment and be sure to have fun!