Pairing a Bluetooth Headset to a PS3
Make sure your Bluetooth headset is fully charged before you begin.
Check your headset instructions for entering "pairing mode". Activate your headsets' "pairing mode" so it can be recognized by the PS3.
On the Cross Media Bar of the PS3 go to the "Settings" tab, then down into "Accessory Settings", then down into "Manage Bluetooth Devices".
With your headset in pairing mode, follow the onscreen instructions and let the PS3 scan for your headset. When your headset is found, follow the prompts and enter a pass key. The pairing should now be complete.
Mic Test and Volume Setting
After pairing a Bluetooth headset, or after plugging in a USB (wired) headset, go to "Accessory Settings" and choose "Audio Device Settings". You can test your headset here.
Your headset should appear as the audio input/output device. If not, just use the D-pad to highlight the Input line, then scroll until you see yours. Any microphone you have used with your PS3 will be listed, but only the current one will be available to select.
Set the "Microphone Level" to 3. You can change the level any time if needed.
Speak into the headset, and the level bar at the top of the screen should move at the sound of your voice.
If your mic doesn't appear there then try pairing it again.