Special Effects - The Photoshop: Professional Retouching and Compositing Tips, Tricks, and Techniques - page 260

Adding Swelling
Here's how to use a couple of tools in the Liquify filter to make it appear as though the
fighter has a swollen eye.
Note
In the more recent Photoshop updates we are able to use the Liquify filter as a
Smart Object but if you don't have this option, simply duplicate the layer you are
going to work on and then use Liquify; that way, your working copy is safe.
1. With the layer containing your subject active, go to Filter > Convert for Smart Fil-
ters, and then to Filter > Liquify ( Figure 4.58 ) .
Figure 4.58
2. In the Liquify Filter properties, select the Advanced Mode checkbox ( Figure 4.59 )
so that all of Liquify's tools are available.