Use a ferromagnetic material such as iron, steel, nickel, or cobalt
Rub the material in one direction with a strong permanent magnet many times
Place the material inside a coil of wire and run electric current through the coil
Keep the current flowing to create an electromagnet
Use a strong magnetic field to align the domains in the material
Heat and cool certain materials in a magnetic field to help retain magnetism
Store the finished magnet away from heat, shock, and strong opposing magnetic fields