Standard C++ doesn't have ways to change the text colour. You could use a library like the WinAPI on windows or ncurses on *nix. You might also be able to use escape codes: http://en.wikipedia.org/wiki/ANSI_escape_code#Colors
#include <iostream>
int main()
{
std::cout << "\033[;1;32mThis text is green.\033[0m" << std::endl;
std::cout << "\033[;1;34mThis text is blue.\033[0m" << std::endl;
std::cout << "\033[;1;31mThis text is red.\033[0m" << std::endl;
}
I'm not really good at this so you better search to find more information.
Using a library is probably a more recommended way.