How to add "Edit Content" link to navigation menu, will edit content of current page

Hi,

I imagine this has been answered before, but I searched for 1/2 hour and couldn't find anything. How do I add the "Edit Content" link to my navigation menu. I'm using a custom theme, so I don't have the click on title to edit page option. I know edit links are generally /node/1/edit or whatnot, but I want a link in the navigation menu that will bring up the current page for editing.

Thanks for any help.