Before removing the cap, shake the vial gently. Remove the vial cap and place it on a flat surface with the top of the cap pointing up. Squeeze the vial to discard the first drop. Wipe both the tip of the control solution vial and the top of the cap with a clean, damp tissue or cloth. Squeeze a drop into the small well on the top of the cap or onto another clean, non-absorbent surface.