That's my department. What camera do you have and what software are you using to edit your videos? Think simple and you will get GREAT results. Think complex and bye bye.
Things you need and things to think about.
1. A good HD camera. Not too expensive. Ebay is the best.
2. IMovie is great to start editing with although not great for sound.
3. Mic. If you can't or don't want to use a mic set up yet then make sure to film yourself close to the camera. This lessens the gain that is heard on output.
4. Lights. Simple. Get a 2 natural daylight lamps with daylight bulbs in them of about 150 watts. You can use a thin sheet to diffuse the light. You can also use aluminum foil to bounce the light.
Did I leave anything out?
Oh well you. You have to be comfortable doing it. It takes practice but it's really conversational.
Hope this helps. This video I recently took about 5 hours to do from start to finish. And yes that is my voice.