The first step is to choose a good toothbrush. You always want to use a soft brush with a small head. A soft brush is hard enough to remove plaque, yet gentle enough not to damage your teeth or gums.
The next issue is to select good toothpaste. In general, any toothpaste that contains Fluoride will do the job, unless you have special needs that are determined by your dentist. Two of the best brands of toothpaste are Colgate Total and Crest Multicare.