Flash CS4 ActionScript 3.0 Tutorial
How to Set Up Your Preferences to Work Smart with Flash ActionScript
There are changes you can make to the default Flash Preferences to improve your workflow.
Open the ActionScript panel (Option/F9 (PC - F9)).
Open the ActionScript panel pull-down menu and make sure Word Wrap is selected. This makes your code "wrap" when it hits the right side of the window. By selecting Word Wrap, none of the code extends beyond the panel's right edge.
Choose Preferences from the ActionScript pull-down menu.
In the dialog box, increase the font size and change the font if desired. Twelve point type is easier to read.
You can also access the ActionScript Preferences by pressing Cmd/u (PC - Ctrl/u) and choosing ActionScript from the menu.