Ok, so vascularity is a visible badge that tags your hard work for all to see. We all like those veins everywhere, I think its a sign of all your hard work..:)

Some people tend to be more vascular naturally due to their genetic makeup, while others that are not genetically blesssed have to work hard at obtaining large veins, just like some have to work twice as hard as obtaining large calves, etc.

Some ways u can increase vascularity are:

Increase Workout Intensity :

Vascularity is increased by raising the blood pressure in your veins and that comes about by hitting your weight training program hard through higher reps, drop sets and supersets, in other words, strive for bigger pumps and don't give your muscles time to recover.

Decrease Body Fat :

Having a high body fat will only keep those veins in hiding. The same way having belly fat will not let your six pack show, same goes for exposing those veins.. you want to be vascular, then drop your body fat.

Eliminate Retained Water:

Many folks make the mistake of avoiding fluids in order to eliminate subcutaneous water. The truth is, if you cut down on fluid intake then your body will instinctively retain water. The correct way to reduce water weight and increase vascularity is to drink more water.

Take Good Vasodilator Supplements:

You can effectively increase vascularity by taking pre-workout supplements that are specifically designed to expand blood vessels. Doing so increases oxygen and nutrient-rich blood to working muscle tissue allowing for greater and more intense pumps. Taking pre-workout supplements high in Creatine, L-Arginine,, Nitric Acid and other vasodilators will help with bulging those veins.

For me drinking a gallon and a half ED of water and keeping up with cardio and keeping bf down has always giving me great results.. so if u want those veins to show follow these tips.