In a nutshell: don’t.

Bad situations to wait until the last minute:

Catching a transcontinental flight

Asking your secret crush to the prom

Applying for a summer internship

Setting customer expectations

Studying for the SATs

Saving for retirement

Giving up smoking

Asking for a raise

Teaching ethical behavior to your kids

Winning a primary

Asking for directions

Sharing an idea

And, for balance, two times when it pays: