Off Camera Flash

So I started experimenting with triggering the speedlight wirelessly with the built-in flash from the Canon 7D.

 

Took a bit of fiddling but I got it to work.

 

Now the big question is how the heck do I tell the built-in flash NOT to fire, to just let the speedlight do it's business.

 

I resoreted to covering the built-in flash with my hand while pressing the shutter as in this particular image, to protect the subject from the hard light.

 

I need to do some research today and find out how exactly do I make it shut up and just trigger the big flash.

 

Anyone has some easy answers? :) I'll take them!

Done