How can a teen male get huge veiny arms?

To get Veiny on your arms or aywhere on your body you have to have low Body fat percentage, and lift weights. It basically comes down to those 2 factors although Genetics also play a role on how veiny you look but just about anyone can get that look if they have low body fat and lift weights. Your diet is also very importnat it has to be very low in fat and rich of veggies fruits and lean protein and good portion sizes. You will find that people who have veiny arms have a very low body fat and almost always work out. Veins are visible because the muscle pushes them out due to muscle growth and less fat under your skin. Its a sign of great vasularity meaning how your blood goes through your arterys and veins.

so lit weight and really cut down the fat in your diet you should see results quickly.