Related:

• You never need a semicolon before an 'end'.
• The bottle is full. You must empty it before you put something else in.
• Use the semicolon properly, always use it where it is appropriate; and never where it isn't.
• Don't put the cart before the horse
• Let's put the blame where it belongs: On somebody else.
• Always put the important before the merely urgent.
• Put brain in gear before using machinery.
• On a Shake-N-Bake or similar product, I saw a sticker saying "Remove this label before baking".
  Now, if they never put this useless sticker on there in the first place, a warning wouldn't have been required, and thus, no sticker....
• When all else fails, put another megavolt through it.