1) If in doubt kill a character.
2) Plot holes can be filled with dead bodies.
3) Nothing screams thriller more than characters screaming for their lives.
4) Car chases and shootouts are mandatory.
5) The hero can’t die, unless you really, really want them to.
6) The bad-guy must die horribly, unless you want them for the sequel. Even then, the sequel could be a zombie thriller.
7) Beloved minor characters must die the most gruesome and pointless of deaths.
8) Minor bad-guys must follow the inverse ninja law.
9) The only reason a gun should ever run out of bullets is if it puts the hero in even more danger.
10) The rules of physics and biology do not apply to the hero, unless it puts them in even more danger.
11) Deus ex machina can only be used once in the story, so use it wisely.
12) If your story hasn’t given your readers a heart attack, rewrite it so that it does.
See also:
http://davidmorrell.net/on-writing/writing-advice/
http://www.creative-writing-now.com/how-to-write-a-thriller.html
http://www.writerscentre.com.au/sydney/thrillerwriting.htm
Tyson Adams 