When you wake up in the morning and the voice often sounds 'woolly', you have been drawing air back and forth over the mucous membranes all night, maybe you have even slept with an open mouth. This may have dried out the mucous membranes. When you wake up and speak, the dried out mucous membranes cannot make the rapid vibrations which produce a sonorous sound, causing the sound to be husky and irregular - known as 'morning voice'.
You should let the natural production of mucous take its course. The mucous membranes will soon be moistened and the voice will sound normal again. If you start to clear your throat which dislodges the mucous off the membranes, they will only produce more to cover the exposed dry area. This makes some singers clear their throat again, compelling the throat to make more mucous. Creating a cycle of clearing and followed by extra mucous production.
Clearing the Throat
When you clear your throat you dislodge the mucous off your vocal chords and lining of your throat. Its not damaging to do this once in a while. It can be essential to remove extra mucous from your windpipe, but it might irritate the lining of your throat especially if you do it every day. Instead allow the mucous to remain there until it has covered the dry spots in your throat. Go ahead and use your voice and disregard the wooly sound. Start by humming or speaking, carefully at first, and soon the rapid vibrations of the vocal cords will shake loose the excess mucous. THere is another safe way to make excess mucous disappear. Closing your mouth and nose and at the same time suck and swallow. (This may also pop or clog your ears so go easy.) This creates a partial vacuum that sucks the excess mucous off the vocal cords.
Prevention and Emergency Aid
Even though a singer's voice might sound as if it is strained or that it has perhaps completely disappeared, it can often be repaired within a few hours. It's best to make certain that no actual damage has been done. A specialist can look at the vocal cords via an endoscope.
If the vocal cords are strained and the specialist reports visible nodules are present the only thing that can be done is resting the voice for 4-6 weeks. That means no talking, especially no whispering, as that takes more effort than talking.
Once the specialist tells you he or she can see no damage then there may be some unconscious restriction of the vocal cords. This may be due to a dry throat or to a lack of strength. If a person is tired or exhausted the voice will likely become strained. In this case quality sleep can heal the voice.
Food and drink do not touch the vocal cords themselves, they are in the larynx and food and drink go down the esophagus. So drinking warm water with lemon or apple cider vinegar can feel soothing and may reduce bacteria in the mouth, but it won't touch the vocal cords themselves. So I still recommend drinking something that feels like it clears the throat, because it's so much better than the roughness of the clearing or coughing action.
Breathing steam can be helpful if your voice is hoarse. Be careful not to burn yourself. Please wait 30 minutes to let the vocal cords rest after breathing in steam. Do not clear, but rather allow the mucous to clear itself with speaking or humming.