Update 4_first_run.rst

tidied up to be easier to understand.

getting_started/step_by_step/4_first_run.rst

@@ -17,8 +17,8 @@ walk across the room, etc.) are very easy to use.
 The game start-up itself is also coordinated using an ESC script.
 
 Scripts are plain text files with an ".esc" extension, created in any text
-editor you choose to use. Create a new ESC script which will be our main game
-script and call it "game.esc". Switch to Godot's **Editor** tab and select
+editor you choose to use. To create a new ESC script which will be our main game
+script, switch to Godot's **Editor** tab and select
 "New Text File" from the "File" menu:
 
 .. image:: img/create_room_newtextfile.png