Coin Cell circuit to blink LED forever

Hi, can someone help me make a led blink forever with coincell. I have a red colour LED with a simple coin cell (used in watch) that I would like to use on my thanksgiving gift. This LED should be blinking forever (atleats for a month). When i connect the LED to coin cell it glows bright but i want it to blink, so how to make the led blink with coin cell ?