When choosing a full body suit for dogs, several factors should be considered to ensure a proper fit and functionality. Start by measuring your dog's length from the base of the neck to the base of the tail, as well as their chest circumference and leg openings. This will help determine the appropriate size of the suit. Consider the purpose of the suit—whether you need protection from cold weather, allergens, or a calming effect. Look for suits made from high-quality, stretchable, and breathable materials that allow for freedom of movement. Ensure the suit has suitable openings for your dog's legs and a secure fastening mechanism that will keep it in place during activities. It's also helpful to check customer reviews and ratings to gauge the durability and comfort of the suit. Lastly, choose a design or color that suits your preferences and reflects your dog's style.