system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How are magnets made?
gpt
To make modern strong neodymium magnets, first you've got to turn what starts out as powdered material into the magnet shape: this is done by pressing powder into a mould. A magnetic field may be used to line up the grains, but it does not hold this field.  
Then the shaped powder is heated and kept at a temperature until the grains start to fuse together without melting in a process known as "sintering".

Now you have a solid lump of neodymium-iron-boron alloy in the shape of the magnet you want, but it isn't magnetic.

To make it magnetic, it is placed inside a coil of wire or "solenoid", which acts as an electromagnet. A current is passed through the coil and a strong magnetic field is produced, which causes the many magnetic "domains" inside the material to align so that when the external magnetic field is removed, the lump of metal has a net magnetic field.

It's as if the magnet is filled with lots of tiny bar magnets. Before the field is applied they are randomly oriented and their fields end up canceling each other out, but when a very strong external field is applied, they move to align with that field, so instead of canceling out, they add together to create a larger stronger magnetic field.