Driving a laser diode with an LM317
The laser diode requires 7 mA and it will drop a maximum of 2.2 volts at that current. If you have a regulated 5 volt supply, you can simply put a 400 ohm, or slightly larger, resistor in series with it. A 1/10 watt or higher power rating for the resistor will be more than sufficient.

Since the laser is infrared, you will not be able to see it with the naked eye. But a clever trick is to look at it with your phone video camera. Most phones are quite sensitive in the infrared range. You can confirm that this works with your phone by trying it with your TV remote. You should see flashes from the IR LED when you are pushing a button on the remote.