A person uses a home blood type testing kit by piercing the tip of the finger with a lancet, collecting a small amount of blood, and applying the blood to a prepared testing card. The blood on the card will then react based on the person's blood type, according to CraigMedical.com.
A home blood type testing kit includes a testing card, a sterile lancet, an alcohol swab, collection sticks and instructions. To use a home blood type testing kit, begin by adding a small amount of water to the four test areas on the testing card. Sanitize the fingertip using the provided alcohol swap, and then use the lancet to pierce the finger. To use the lancet, rest the hand on a flat surface, apply the lancet to the tip of the finger and push down on the trigger until it clicks. Blood will begin flowing from the finger. Collect this blood in the four provided collection sticks, then spread each sample into one of the four test areas on the testing card. Once this is done, the blood will begin to react with the card by clumping in certain test squares. Refer to the instructions included in the kit to determine the blood type denoted by the testing card results, says CraigMedical.com.