what function do i use to print out a menu? the menu was created in the admin
You can use menu_tree_all_data function. 

E.g.

$tree = menu_tree_all_data('machine-name-of-menu');
//menu_tree_add_active_path($tree);
print drupal_render(menu_tree_output($tree));


For more info go through the function documentation.

menu_tree_add_active_path will be found here. It will be used when you want to add active trail on menu.