Like the name implies, the diagram will involve a box. Specifically, it's a rectangle that has a vertical line somewhere inside it. The vertical line does not have to be at the midpoint. The vertical line represents the median. The left and right edges of the rectangle represent Q1 and Q3 in that order.
On either side of the rectangle are horizontal lines that are called whiskers. They stretch to the min and max (left and right sides respectively). This is when there aren't any outliers. If there are outliers, then there would be isolated island points not connected to the whiskers or the box.
