Pijush, a few tips for phone interviews:
1. Try and do it from a land line. We're actually seeing clients specifically request that candidates take calls from a land line. A lot of people are wary of cell phone reception.
2. Speak clearly -- I know it goes without saying but make a conscious effort.
3. Don't interrupt the interviewer -- again, goes without saying but in certain cultures (or perhaps certain regions of the world) it's pretty common to interrupt others. When I grew up in India, we did it all the time and it was just how people communicated....at least the people I spoke with. Now, I'm a lot more aware of that and really notice it when someone does it. Just something to keep in mind.
4. Be relaxed and rested -- again, verrrry obvious but I don't know if everyone does it.