√ Allow your pet (dog, cat) to spend the first two months with its mother and her siblings to be well socialized. Also introduce stimuli which they will become familiar with later in their adult stage (people, smells, noise, …).
√ Do not caress your dog (in order to calm him down) when he is barking or is aggressive.  This action causes him to become more restless and aggressive because he interprets the caress as a reward.
√ The reward or the “no” information must be applied immediately following the action performed by the pet and introduced to the pet before punishment.  Although after a while this has no meaning.  Study how to control your frustration and prove to be more intelligent by swapping punishment for reward, achieving the same result … you can do it!
√ It is not easy for a pet to bite a person. The correct treatment for aggressiveness can be found in its etiology (origin), because there can be many different causes.  Visit your Veterinarian if this happens!
√ Reach a common agreement with all members of the family that have a link to the animal to determine what is permissible or not to the animal.
√ Train your dog in a skill, it will help you increase the  link with him and dissuade unwanted visible behaviors.  You can give him an order if he is doing something wrong.
√ “The aim of ethology is to describe the repertoire of characteristic behaviors of the species and, for each one of the behaviors described, explain their control, their ontogeny, their function and their evolution”. (X.Manteca).
√ The manifestation of what we see (behavioral problem) can be caused by an organic problem (health problem), its assessment and discarding should be done by a Veterinarian.
√ Support pharmacological therapy with behavioral therapy and vice versa, not waiting for “miraculous” pharmacological results.
Be curious, empathetic and don’t forget to visit your veterinary if your dog has behaviour problems.