Place the venipuncture device over the dark line (the target vein) just below the lighted spot between the venoscope's arms.
Angle the device 20 or 25 degrees downward, and insert the needle. If the skin bulges, gently stretch it on the underside until you successfully enter the vein. If necessary, pull the needle back slightly, and move it a few millimeters to the right or left to penetrate a vein.