The following are some ways you can prevent gum disease:
The first step in prevention is knowing the signs and symptoms so that should you already have a problem, or be on the road to a problem you can course correct, and quickly.

Signs and symptoms
Although the symptoms of periodontal or in other words, gum disease often are subtle, the condition is not entirely without warning signs. Certain symptoms may point to some form of the disease, and your dentist will know how serious they are. So, pay attention to these symptoms as they can act as a warning that without action to correct the problem there will be a major problem. They include:
    gums that bleed during and after toothbrushing, unless this is caused by using too hard of bristles, or too hard of strokes, this can indicate weakened or diseased gums, so talk to your dentist.
    red, swollen or tender gums, if your gums are red, swollen, or tender then you likely have an infection. If left untreated this can lead to gum disease
    persistent bad breath or bad taste in the mouth, bad breath is often caused by bacteria or gingivitis, which leads to more serious gum disease, talk to your dentist.
    receding gums, receding gums are often a result of gum disease, so if you notice your gums are receding, get them checked out.
    formation of deep pockets between teeth and gums, these deep pockets hold bacteria, and allow it to fester, this can lead to gum disease.
    loose or shifting teeth, once again, a sign that you may be on the road to gum disease
    changes in the way teeth fit together on biting, or in the fit of partial dentures.

So, now that you know what to look out for that may indicate you have gum disease, let's look at the methods of prevention you should be using:
    Brush your teeth properly twice a day. Talk to your dentist about what type of tooth brush, size head, bristles, etc. to use. Brushing your teeth thoroughly removes plaque from the surface before it hardens and leads to gum disease.
    Use a fluoride toothpaste. Using a toothpaste with fluoride helps to prevent decay.
    Floss your teeth daily. Flossing is the most overlooked step of oral hygiene and one of the most important steps to avoid gum disease. Flossing is the only way to remove plaque from in between your teeth that a toothbrush can't reach, so don't neglect your daily floss.
    Use a mouth rinse or mouth wash. It is important to regularly use an antimicrobial mouth rinse, this is the type of mouth wash that does not just mask bad breath, but actually helps you to fight bacteria, plaque etc Listerine is a good choice.
    Visit your dentist for regular check ups. You should at the minimum visit your dentist semi-annually. If you smoke, drink, are pregnant, diabetic, etc. more frequent visits are wise. Visiting your dentist on a regular basis is the best way to make sure that your teeth and gums stay healthy.

Gum disease (periodontal disease) leads to bad breath, oral bone loss, and tooth loss. if left untreated, it can even cause medical problems such as diabetic complications, strokes and pre-mature births. So, do not be ignorant to gum disease, take steps of prevention, watch for signs, and talk to your dentist if you have any questions.