Future Phlebotomist?

This morning Adam came up to me with a tourniquet. (You may be asking why we have a tourniquet--they are great for opening jars! ) He tied it (loosely) around my wrist. Then he proceeded to feel for veins in my hand. He told me that this is what people do when they are going to take your blood.

My question is: How does he know this? He had some blood drawn last October, but that was 9 months ago! Does he remember, or just have this knowledge?

He also took the picture :)