Any tip or combination of tips can be used to improve your voice, your style, or fix a sore throat. Some of these represent ideal situations, which many certainly do not live in. Others represent the complete opposite of things you may have heard.

Review them. Anything that is highlighted has already been addressed. You need only to click on the tip to view to question and the answer. I no loger answer questions, but you can still join my discussion list and get the opinions of the 1000 members of the group.

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Plan ahead
Sore throat? Try an apple or pear (or their juices)

Don't do anything that will hurt your voice in any way
When looking for a teacher, ask about his/her backgroud in music, and whether they are willing to help you learn how to sing something other than their style of singing
Just because a singer sounds nice doesn't mean s/he can sing
When you are learning to sing, you are doing it to find out what your voice is capable of, not someone else's; be happy with what you have
To those who want to sing pop music: There is nothing wrong with learning classical

To those who wish to sing classical: There is nothing wrong with learning popular
You are not the person on the radio-don't try to imitate them unless you are trying to learn something
Don't inhale any kind of smoke at any time whatsoever
Reason: Smoke sticks to and burns your vocal cords.
Related Question #1
Don't drink
Don't do drugs

Don't allow people to come at your vocal cords with sharp instruments. In other words: Don't allow doctors to perform surgery on your vocal cords, as there is a possibility you may never sing again after this. The only way to not have vocal problems is to not do harm to your voice in the first place, a skill which isn't taught due to lack of information.
No more yelling
You can forget ice-cold drinks unless you have some sort of trauma to the throat area, i.e. tonsils removed, that sort fo thing.
Reason: It tightens up your vocal cords. They must be warm and loose in order for you to sing properly.
Don't talk too much
Reason: It wears down your vocal cords.
Try to stay away from a lot of dust

Try to cough a little quieter
Don't sing in groups, choirs, etc.
Reason: Blending with other people can throw off your ear. Choruses don't usually stay in key.
Don't sing any song out of you range
No more than 3 performances per week
Don't use vibrato

Don't dance and sing at the same time
Don't sing your loudest for extended periods of time
Ask as many questions of as many people as you can about singing
Don't go to a vocal coach who is only a vocal coach because he hurt his voice and coud not fix it, unless he is willing to explain to you how he hurt his voice, and how you can avoid the same fate
Reason: What they teach you will eventually hurt your voice in the same way it hurt theirs
Keep away from air conditioning for at least two hours before a performance

Get to know and understand the organs involved in singing
Singing will help to cure a sore throat that is not the result of oversinging or overtalking
Practice as slowly and softly as possible
Learn every style of singing you can
Dairy products cause phlegm

Singing helps to get rid of phlegm
Keep a mint or hard candy handy
When singing, make sure you know what the song is about by knowing what all the words mean and what is going on in the music.
A dictionary of english and english to other languages can be found here
If you must sing in a group, make sure you know what the other voices are doing
Know what the music is doing

Contrary to classical tradition, taking pictures is not a distraction
It is harder to make an audience sit in quiet awe than it is to start a party
Play to the back of the crowd
Being hoarse in the morning does not mean you will be hoarse in the evening
After performing, place a warm, wet towel around your neck and do not speak for 10 minutes

Gargle with warm water containing 1/2 tsp each of salt and baking soda
Try to wear only one fabric on stage
Reason: Those lights get hot
Learning how to sing well takes time. There are no shortcuts.
Try to make as little air as possible come out of your mouth when you are singing a musical phrase
Train your ears by playing only the first note of a musical exercise

Always take one day a week off
Unless it's called for, always stand with good posture (this does not mean standing stiffly) when you sing
Any move you make will affect the sound you are trying to produce
Keep the tip of you tongue below your teeth
Don't exert yourself the day before a performance