This quick look at speedlites focuses on the Canon 430EX II and the 600EX-RT. How to synchronize them without pocket-wizards.
To get started you need your flashes and fresh batteries.
You may also want to turn off the sleep mode.
Starting with the 480, press and hold the zoom/z button until display is as below
Now press and hold the mode button, to switch to manual.
When properly set the display will look like this.
Now that the slave is set, set up the master.
The 600 is just as easy to set.
Cycle through the modes with the z lighting bolt button until you see lightning bolt in top right, and you are in master (green screen)
Now change the mode to manual by pressing and holding the mode button.
When properly set the display will look as above.
You can change which channel you are set to, just be sure they are the same on both flashes.
When set as above both flashes will fire at the same time.
Hope that sheds some light on the issue.
Cheers.