Canon EOS 60D Instruction Manual page 141

Setting [E-TTL II meter.] to [Evaluative] is recommended.
Even if you disable the built-in flash from firing, it will still fire to control
the slave unit. Depending on shooting conditions, the flash firing for
slave unit control may be visible in the picture.
The slave unit cannot fire a test flash.
Select [Wireless func.].
5
For [Wireless func.], select [0],
then press <0>.
Under [Wireless func.], [Channel],
etc., will be displayed.
Set [Channel].
6
Set the channel (1-4) to the same one
as the slave unit.
Select [Firing group].
7
For [Firing group], select [1All],
then press <0>.
Take the picture.
8
As with normal flash shooting, you
can set the camera and take the
picture in the same way.
To terminate wireless flash shooting,
set [Wireless func.] to [Disable].
Using Wireless FlashN
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