Some practical considerations:
1. Avoid noisy rooms where your microphone will pick up ambient noise. Do not have the radio playing in the background.
2. Allow for plenty of light in the room so the mentee can see you well.
3. Do not wear any clothing with tight patterns or pin stripes. This causes an optical illusion called a moiré pattern which makes your image look distorted.
4. Direct cable or fiber optic is better than a wireless connection. There is more of a lag time when using a wireless connection.
5. Webcams – See the following URL for reviews.
http://reviews.cnet.com/4566-6502_7-0.html