What are the best practices for Vocalists or Singers

When you start learning to sing or when you want to take your voice to next level, there are certain things which comes to mind. Are there certain best practices, exercieses, strategies which beneficial and will help be become a better singer ?.
What are the best practices for improving a performance?. What concepts beginners need to know and how to apply exercises correctly. ?
A lot of  answers related to questions above (practice breathing, practice scales, sing along with recordings) are obvious. At the same time, its like telling an athelete how to become a better athelete and run even faster. The Answer is simple, Run everyday , practice more , apply more rigour to your practice and you will be running faster an in Singing - it would mean singing better. 
There are a lot of techinques, tips which will qualify as a "best practice" in singing. Let me just give you a glimpse of that.
First lets understand the vocal anatomy. Your vocal folds are housed in your larynx. This is your Adam's Apple if you're a man, but women can feel the notch on the front of their larynxes, too. Your larynx is super-important to your singing, and whatever you're doing, an awareness of it is vital (because that's where it all comes from). The rest of your throat, pretty much the area above your larynx to the opening of your lips is called the vocal tract. Like any tube, you can imagine it bounded on the top and bottom by two different surfaces. In this case, the lower boundary is the tongue (which has a massive base that you can feel if you reach above your larynx to where one might have a double-chin), and the upper boundary is the pharynx (major hand-waving here, as it's more complicated, but for these purposes that'll do).
The above will form your anatomy when singing. The big subglottal player is breath. The breath mechanism is often misunderstood, and there are disagreements on what constitutes proper support. Suffice it to say that people talk about these muscles a lot, but most of them aren't under conscious control (e.g. the diaphragm). That said, when you inhale, there are basically three big areas of your body that can move: your shoulders, your ribs, and your abdominal region. Likewise when you exhale.
So when you exercises, some of the best practices can be
1. Practice inhaling. It's helpful to get good at this. When you inhale, try to get the highest ratio of movement to effort in your ribs and abdominals (i.e. without a great feeling of exertion, feel a great deal of expansion in these areas). Limit movement in the shoulders.
2. Practice exhaling. Lots of beginning singers focus on getting the perfect inhale, but it's much easier to have problems with the exhale. Make sure you're not holding your breath, make sure you don't feel a lot of supraglottal pressure building up (this would feel like you're lifting something heavy), and make sure your ribs and abdominal muscles feel relaxed and free.
3. The size and shape of your vocal tract is literally what determines your tone color. Some of this is innate (OK, most of it), but a portion of it is in your control. Yawn; you just felt your pharynx make space. Make a kissy face; your vocal tract just lengthened at the lips. Breathe in through your nose like you're smelling flowers; your larynx just descended. All of these things make your voice darker (and their converses make your voice brighter, though this is less effective). Singers are vocal tract sculptors. Become an expert with your clay.
4. Practice keeping your tongue, your jaw, your neck, and your pharynx (once you can control it) loose. The looser they can get, the better off you'll be.
5. The longer your vocal tract , the more protected your voice will be. This is a big reason that opera singers sing the way they do, but it's just as applicable and important to every style. If you're doing something that starts to feel scratchy or weird, lengthen your vocal tract.
A general guideline which applies to all singing exercises is  - If it still hurts, stop.
There are many other things which are required to be a better singer. However I would say that you move forward only when you have mastered the above. So if you feel you are doing a good job with breathinig and can sing decently good, then the next step would be to hire a good teacher. 
Some of the other BEST Practices are 
  1.  Record your own voice, listening to your own voice will give you the best possible feedback. If you dont like what you are listening then you are far from being a good singer, You will need lot more practice. 
  2.  Exercises are best applied with feedback from someone with an intimate understanding of vocal mechanisms and a good ear. Speaking of which, there are computer programs with which you can train your ear to be more accurate (check out EarMaster, for instance).
  3. Always sing as if you're performing. Having said that never practice while driving, walking. When you sing sub-standard all day , how can you deliver great performance. Anytime you sing, it should be like the final performance or DONT SING.
  4. Your audience can tell how you feel about what you're singing. I know many singers who keep going on and on while their audience is bored. No one wants to tell you upfront, so you must learn to be aware of the body language of your audience and change your singing according to that, or if its too much even stop singing.
  5. Never stress yourself or Push to much, Always Warm up before the practice. Dont try too much to get a Vibrato. Vibrato should come naturally. When you get it right once, check under what conditions you got it right and try to repeat that. 
  6. Beyond learning to breath, lie down, put heavy books on your diaphragm, deep breath should lift the books, sing ha-ha-ha-ha-ha.
  7. Learn from your favorite vocalists - 1) emulating the things about their vocals youI liked; 2) harmonizing with them until you have blended. What do you like about their voice, Is it the warmth or the nimbleness or the throw of the words. You must be able to identify these. While it's satisfying to learn to imitate your favorite singers, the real key here is using the practice of imitation to learn about what it takes to make different sounds with your voice.  Once you have learned to imitate a few people, you can start combining the sounds you particularly like to build your own style and interpretations of songs.
  8. A good part of singing is confidence.  If you have confidence, you produce a strong tone, you stay in control physically, you can keep your presence.  When you lose confidence, your breathing and your physical instrument suffers... which causes you to lose confidence... which causes a spiral away from the sound you want to make.
  9. Finally I would like to mention that if possible give live performances even when you think you are not ready. A mistake you make in live performance will have a great impact on you and you will not repeat that again. This way you will keep correcting yourself with every performance. If there is an opportunity for you to sing in front of live audience do that , there is nothing like practicing live ( or learning on the job). If you get feedback from the audience and if its positive, it will boost your confidence. I started of with live performance even before I knew anything about singing, then I kept improving and became a great singer.