Wandering around the house doing last minute things whilst brushing our teeth, or maybe you do it in the shower. Either way you aren't paying attention, I'll bet you missed a few bits. The best brushing is methodical. Lets start with the basics, get yourself a medium bristled toothbrush and a fluoride toothpaste. They can be as fancy as you like or as plain as can be, as long as the toothpaste has fluoride in you're sitting pretty.
Apply a strip of toothpaste along the brush and wet it if you like. Split your mouth into 4, upper left and right, and lower left and right. Start in a different quadrant each time you brush to ensure one area doesn't get all the attention. Clean a whole quadrant before moving on to the next. Start at one quadrant and gently move the brush in a circular motion over the surface of the tooth for a few seconds and move on to the next tooth. Continue doing this for all the outer surfaces. Next, move the brush head in gentle circular motions along the inner surfaces of all teeth in that quadrant, concentrating on the insides of your lower front teeth as this is where tartar is most likely to develop and the area is often neglected. Don't forget to clean the biting surfaces of your teeth, these are full of pits and fissures, or 'rivers' where debris can gather and decay can begin. Remember your back teeth too, if you brush in front of a mirror and work methodically then you can ensure you won't miss any surfaces or plaque deposits. Once you've finished, spit out, but don't rinse your mouth. The longer the fluoride is on your teeth the better.
Remember to be gentle, plaque has the consistency of blancmange, its easy to remove with a brush. Staining and tartar will have to be removed by a dentist, your hard scrubbing only serves to wear away your gums and enamel, causing sensitivity and gum recession.
It is recommended that you angle the toothbrush at 45° towards the gum. If you look at the picture to the left you can see that if a toothbrush is held flat there are areas between the teeth being missed, these are hi-lighted in the red circles. But if you angle the toothbrush towards the gum the bristles can easily fit in between the gaps and give you a better brush. If you are having trouble remembering which way to angle the brush then the simple rhyme: "Uppers towards the nose, lowers towards the toes" Should serve. Whilst this method does clean more in between surfaces of the teeth than the flat brush it does not replace flossing and other inter-dental cleaning methods.