There are no settings you need to change on the camera.
When the transmitter(tx) is mounted to the hotshoe on the camera, the press of your shutter should be sending a signal to the hotshoe, then in turn the tx.
Once the tx gets the signal from the camera's hotshoe, it *SHOULD* send the signal to the receivers(rx).
Assuming the tx and the rxs are on the same channel, the flashes should go off.
If they are firing when you hit the tx test button, I would assume there is an issue somewhere between the camera hotshoe and the transmitter contact (the little ball on the bottom of the tx), perhaps a bad contact or connection. Try mounting a compatible flash unit to your camera hotshoe and see if it fires correctly, if it does, it is def a problem with your tx. You may want to try a new battery in the tx.
I must caution you from personal experience, the ebay triggers are not known for their outstanding craftsmanship, reliability, or functionality (mine won't reliable fire a 430EX), but with a few mods, they can be improved upon (although not an earthshattering improvement). That said, they are by no means a bad learning tool, but do NOT depend on them in an important situation (i.e. paid jobs, once in a lifetime situations, etc).
I've been playing around with the AlienBee CyberSyncs for the last 2 days, so far these are far and away better than the Cactus/eBay triggers; and they are 1/3 the price of a PW Plus II. So you may want to consider upgrading if your problems continue.
In addition to the Cybersyncs, there are also Skyports, Radiopoppers, and the almighty PocketWizards (PW). All of which are good upgrades when you are ready (and have the $$$).