Certainly, you would want to include information about the slave trade, on which the "triangular trade" (a phrase that has fallen out of favor with historians) was based. You could indicate where in West Africa slaves actually came from. You could illustrate the difficulty of the Middle Passage using images like the plan of the slave ship Brookes. You could create some sort of visual that shows where slaves actually went by percentage, and what cash crops they were involved in producing. You might discuss some of the other trade goods involved in the Atlantic economy (i.e. items exported to American colonies.) Finally, you might talk about the items traded between the North American colonies and the West Indies, like building materials and foodstuffs. Your project should emphasize how complicated this trade network was above all.