Emphasis is a design principle which occurs any time a component of a composition is given dominance. In other words, the designer makes part of the work stand out, in order to draw the viewer’s eye there first.
Choose an object to draw (either from real life or from a photograph). Fill the whole page with your drawing, but find a way to bring EMPHASIS to the object you chose. It could be with scale (maybe the object is the largest thing in the drawing- think worm’s eye view) or it could be with contrast (maybe the object is dark and everything else is light or vice-versa), or with color, or position, or by using leading lines… there are endless ways of creating emphasis.