During the procedure
A cholesterol test is a blood test, usually done in the morning since you'll need to fast for the most accurate results. Blood is drawn from a vein, usually from your arm. Before the needle is inserted, the puncture site is cleaned with antiseptic and an elastic band is wrapped around your upper arm. This causes the veins in your arm to fill with blood.
After the needle is inserted, a small amount of blood is collected into a vial or syringe. The band is then removed to restore circulation, and blood continues to flow into the vial. Once enough blood is collected, the needle is removed and the puncture site is covered with a bandage.
The entire procedure will likely last a couple of minutes. It's relatively painless.
After the procedure
There are no special precautions you need to take after your cholesterol test. You should be able to drive yourself home and do all your normal activities. You may want to bring a snack to eat after your cholesterol test is done, if you've been fasting.