I presume you're asking about what's commonly known
as spit shining.
As a former cadet, I can tell you that the procedures you
hear
about lighting the polish on fire to liquefy it (to get lots
of polish on in one application) or lighting your boots
on fire, are generally more work than they're worth.
You're better off just perfecting your spit shine technique.
See this link;
http://www.cadetstuff.org/how_to/200201_elliott_bulling.htm