1. Say "aaaah" with your normal voice pitch, feel where it's coming from. From my experience singing, your high voice comes from the area in or slightly above your larynx.
2. Now put your hand on the neck area just above your breastbone, and bring your voice to as low a pitch as possible. Keep going lower and lower and you will feel the bass vibrating in this area, this is where your bass range comes from, essentially anywhere below your larynx.
3. Visualize your voice coming from this area while you do step 2, and take your hand off your neck, keep doing the "aaah noise" and say a few sentences in this new voice, warm up to it.
4. Project your voice with your stomach, but not too much, you don't want people to think your voice is forced, do you?:lol:

I'm no vocal coach, but I gave a dude in my university these tips a while back and his voice seems a lot more confident and assertive now, hope it works for you.

Seán

Great post man! I feel like my voice is more high pitched then i would like. Im going to practice this.

I'm gonna practice it too. I dunno which was first, the chicken or the egg, but my voice doesn't get listened to. When I speak too casually, like when I'm in a cheerful or childish mood, sometimes it lowers to a little high-pitched, soft voice, and when I care about how I speak, it's pretty deep, but I sound like a duck. (I heard myself on record) So my voice is not as cool as I'd like it. I'll definitely practice this. Thanks.

very helpfull thankyou

this is pretty helpful. Ironically i noticed the same thing that its where your voice comes from that effects the tone.