Breathe from your diaphragm
Speak more slowly
Lower your larynx naturally
Relax your throat and jaw
Practice humming in a comfortable low range
Do vocal warm-ups daily
Stay hydrated
Avoid straining or forcing your voice lower
Improve posture
Reduce tension in your neck and shoulders
Use chest resonance when speaking
Record and monitor your voice
Avoid smoking and excessive alcohol
Get enough sleep
See a speech therapist or vocal coach if needed