I was just wondering how Presidential Primaries were indirect.

See this:... Primaries may be direct or indirect. A direct primary, which is now used in some form in all U.S. states, functions as a preliminary election whereby voters decide their party's candidates. In an indirect primary, voters elect delegates who choose the party's candidates at a nominating convention.
indirect primary (politics) -- Britannica Online Encyclopedia (http://www.britannica.com/eb/topic-286220/indirect-primary)