Use any tooth brushing method that is comfortable, but do not scrub hard back and forth. Small circular motions and short back and forth motions work well. Rinse.
To prevent decay, it's what's on the toothbrush that counts. Use fluoride toothpaste. Fluoride is what protects teeth from decay.
Brush the tongue for a fresh feeling! Rinse again.
Remember: Food residues, especially sweets, provide nutrients for the germs that cause tooth decay, as well as those that cause gum disease. That's why it is important to remove all food residues, as well as plaque, from teeth. Remove plaque at least once a day--twice a day is better. If you brush and floss once daily, do it before going to bed.