Choosing a pet is a big responsibility and a long-term commitment. Remember your adopted friend will require food, water, exercise, veterinarian care as well as your love and attention.
Visit the Animal Welfare Kennels and see which dog/cat appeals to you and from whom you get a warm feeling. Make sure that the animal will fit into your lifestyle e.g. do not choose a big dog if you are unable to take it for long walks and you do not have a big space for it to live.