What do you guys normally do to warm-up your vocals?
My problem is that I feel like there’s something in my throat when I sing at times. (I’m not sure if you call that mucus). Hence my voice doesn’t sound very ‘clear’ when I sing.
But at other times, my voice seems clear and nice.
Why does this happen? Is it because I do not “warm-up” my vocals or something?

Thanks for the feedback guys.