It's really difficult to explain how to sing over the internet. Even in person, it's difficult because you can't really "show" a person how your vocal chords work.

My advice would be to try and relax your neck/throat muscles as much as you can. And just sing for longer each time in small increments. The voice is a muscle, you should train it as such.

Also, don't be afraid to push the boundaries! I've increased my vocal range by a helluva lot just by experimenting. But if it starts to hurt then obviously you need to stop.

Check out the results of my singing practice here: http://www.facebook.com/TLoKBand

I used to have a voice like a Backstreet Boy. Hahahah.

u mean doing scale exercises with the voice?