Telephonic HR round next week: how do you sound confident on a call?

Got a call from a recruiter for a telephonic HR round next week. It's my first phone interview. In person I use my hands and expressions a lot, and on a call I feel like I lose all of that and just sound flat.

My plan so far:

• Take it in the one quiet room in the house, with the fan off and the door closed.
• Keep my résumé and a few bullet points in front of me, but not a full script.
• Sit up straight, maybe even stand, because people say it changes your voice.

What else should I prepare for? Are phone screenings mostly the standard questions (about yourself, relocation, notice period, salary expectation), or do they go deeper? And how do you handle silence on a call without it sounding like the line dropped?