fetal Doppler! couldn't find heartbeat. anyone have tips for finding it?

V • Mommy to 2 precious baby boys 💕
So I heard it today at doc but my husband wanted to hear it at home since he didn't go with me. We tried looking for it and couldn't find it. I'm not gonna try again for like another week but just wanted to see if anyone had any tips and tricks for us 🤗