The table below lists the key bindings in Symex mode. You can always use Emacs’s C-h k to learn what a key does, of course, as another way to learn these bindings. But as the underlying commands are wrapped by Lithium, you would need to visually parse through the Lithium logic to spot the wrapped command in the result.
Finally, the Animated Guide to Symex shows each of these commands in action and includes tips on their usage.