How to op myself minecraft 1.7.2?

Go into the console and type: op insertusernamehere

When you run your server, the window should pop up and it should say that its loading the map up, if you press on it you can write in the windows (console), you must be ingame to op yourself. Go in your server, open the console and write: op [nickname]. Hope this helps.

Type /op [your username]