I had to follow up with a company a few days ago. This is what I wrote. They got back to me in a few hours.

Dear <name>,

Thank you again for the opportunity to speak with you regarding the <position name> position on <date you interviewed>.

From our conversation, I had hoped to hear back regarding the next step of the interview process. I am excited about this position and would appreciate knowing if I have been selected for the next step.

I understand you are busy. Thank you for your time,

<your name>