Anyone have any tips for using a Doppler? (Plus sized)

Karrie
I know since we have some extra cushion it can be harder to find the heart beat so I'm wondering if anyone has any tips! I'm only 8w3d so it may be early still but I would just really like to try hard to find it. This is my rainbow so I'm freaking over everything and finding the heartbeat would ease my mind! I have the sonoline B by the way.