What is the best way to prevent and treat Shin Splints?

It depends on what you mean by the term "shin splints". Most people mean "leg pain associated with exercise". Unfortunately, there are many causes for this, and the first step is an accurate diagnosis of what is causing the problem. For this you should see a knowledgeable provider for evaluation.

The most common cause of "shin splints" is stress on the medial tibial border with running/walking. This usually is a result of doing "too much (exercise), too soon" coupled with some mechanical factors that predispose to the condition. Cutting back on activity, ice packs 2 or 3 times daily for 20-30 minutes each time, stretching the calf muscles slowly and gently, and perhaps evaluating your footwear may help.

However, "shin splints" can also be caused by stress fracture, muscular tears and strains, "compartment syndrome" (where the pressure inside a muscular compartment increases with exercise to the point where circulation and nerve function within the compartment are compromised), and a host of other problems. So, get the symptoms accurately evaluated, and your provider will be able to give you specific advice based on what is causing YOUR symptoms.