The best first step will be getting a diagnosis to determine what type of vascular birthmark it is, and then the doctor can suggest treatment options.
Port wine stains on the face can be treated at a young age with a yellow pulsed dye laser for best results.
Here is some information about Pulsed Dye Laser Treatment from the Children’s Hospital of Pitsburgh:
Also, here is some more info I found on the different types of vascular birthmark, specifically a common type known as the haemangioma which comes in multiple varieties listed below:
Types of haemangiomas include:
Strawberry haemangiomas (also called strawberry mark, naevus vascularis, capillary haemangioma, haemangioma simplex) may appear anywhere on the body, but are most common on the face, scalp, back, or chest. They consist of small, closely packed blood vessels. They may be absent at birth, and develop after several weeks. They usually grow rapidly, remain a fixed size, and then subside. In most cases, strawberry haemangiomas disappear by the time a child is 9 years old. Some slight discolouration or puckering of the skin may remain at the site of the haemangioma.
Cavernous haemangiomas (also called angioma cavernosum or cavernoma) are similar to strawberry haemangiomas but are more deeply situated. They may appear as a red-blue spongy mass of tissue filled with blood. Some of these lesions may disappear on their own – usually as a child approaches school age.
Port-wine stains are flat purple-to-red birthmarks made of dilated blood capillaries. These birthmarks occur most often on the face and may vary in size. Port-wine stains are often permanent (unless treated).
Salmon patches (also called stork bites) appear on 30%-50% of newborn babies. These marks are small blood vessels (capillaries) that are visible through the skin. They are most common on the forehead, eyelids, upper lip, between the eyebrows, and the back of the neck. Often, these marks fade as the infant grows.