What are the precautions I should take to avoid psoriasis?

Psoriasis. No way to prevent if this is going to happen. If your body is going to get psoriasis, there is really no way to prevent. Basically, keeping a good diet, exercise, not smoking, drinking or drug use can always help to keep the body healthier. A safe weight too.
Not many answers. Psoriasis is a skin disease involving an abnormal immune response. Some individuals may have increased (inherited) risk of developing this condition and it is not clear what triggers it. Exacerbations in those who have already developed psoriasis are often associated to stress and inflammation, and treatment includes meds that modulate the immunity, in addition to uv light.