Press "TAB" to go to Edit Mode. You can also do this by going to "UV EDITING" but I won't recommend that. TAB is faster. See the points on screen? These are your VERTICES. You can move them around. Press E to extrude (Make them pop out/bigger/move around) and then press X,Y,Z if you wish to move them around on those axes. Press S if you wish to scale them (make them bigger/smaller. Usually requires a selection, a shaded-in shape, to work perfectly.).
Hope this tip helps, even if a little.