Someone asked me just the other day about how to cure a "froggy" voice.
Usually the "froggy" voice comes from a tightening of the throat while singing. Vocalists should try to keep the throat as open as possible. This "openness" is easier to achieve once you know what it feels like to have an open throat.
A great way to introduce this feeling is to breathe on a mirror or window, and make it foggy. Pay attention to what the throat feels like while breathing. Try to isolate the muscles involved and work on "muscle memorization" so that you can recreate this openness during singing.
Now begin singing a simple warm-up. Does the throat still feel open? If not, go back to the mirror and try it again. Do this over and over until the throat begins to open repeatedly.
During song performance, keep the open throat in mind! This can help take your voice from froggy to foggy!!