Generally speaking, hold down the "function" (whatever the big button is) on the headset and hold it for like 5-10 seconds, which will turn it on and force it to be discoverable / pairing mode. it should flash the LED and make a funny tone (not the startup tone)
Then make sure Bluetooth is on, and then do " scan for devices" and it should pick up the headset.
Then you'll need to enter the pairing code (usually 1234)
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Kasey C, PC guru since Apple II days
I don't suffer from insanity. I enjoy every minute of it.