You can rub a magnet along the metal in one direction for a bunch of times (the more the better), and that will magnetize it to some degree, but its not permanent and will demagnetize if it is hit hard with something.
Also, to magnetise something like a nail, if you point one end north, and hit the other end with a hammer it should weakly magnetise it. Unfortunately it doesn't work every time.
By creating an electromagnetic field using electricity and then taking a ferromagnetic material and placing it in that field, the material will pick up some of the magnetism. And for more effect, create a bigger field. Plus, if the material to be magnetized is heated really hot (above its Curie point, TC) and then put in the field and then allowed to cool while in the field, it will really pick up the magnetism! This is how commercial permanent magnets are usually made.