Tying a bow tie is one of those things that might not be an every day occurrence, but I can assure you that it will likely come in handy at some point in your life. I mean, everyone should attend a gala every now and again (right?!) Luckily for the bow tie inept amongst us (ahem, myself), we have people like Annie Dean who can walk us through all of these adorable life skills.
Pull B up and under A, forming a loose overhand knot. Tighten if necessary.