Unthread the collar out the transmitter, then unscrew the transmitter, battery's will be inside, there should be a 2 wee arrows pointing inwards to a dot on the transmitter. Hold your magnet hammer lol over the dot and swipe to turn on an off, the sliding knobs at each side are on off and locate search. Hold your locator flat in your hand and put it in search then walk around and it'll find collar, when at smallest reading switch to locate on side slides switch and point it to floor and put bottom on floor keep moving about till you find shallowest reading on LEDs and your in, I think the twis