How do you make a black hole?

Question

How do you make a black hole?

Answer 1

a supernova star has 2 explode.

Answer 2

Cram a bunch of matter into a space smaller than the Schwarzschild Radius of that mass.  A collapsing neutron star is the best known candidate.  But some argue that relativistic time dilation prevents the formation of a black hole from ever happening.