Constructing a 12v circuit and need help!?

Need to figure out how I can build a 12v circuit similar to a Normally open, timed closed relay. I have been told I need a 555 timer, a transistor (BC107B) and a normal 12v car relay. Been trying to figure this out for a while but got a headache just trying to figure this out. Got some knowledge of electronics but... show more Need to figure out how I can build a 12v circuit similar to a Normally open, timed closed relay. I have been told I need a 555 timer, a transistor (BC107B) and a normal 12v car relay. Been trying to figure this out for a while but got a headache just trying to figure this out. Got some knowledge of electronics but as you might of guessed I'm not to educated so just need help putting things into place. Would be a massive help if someone can show me a schematic of how I can do this.
Update: I have an existing third party module that is a black box. It runs on 12v car battery. Pressing a momentary switch causes the module to activate, playing the sound and flashing a number of LEDs in sequence. The problem is that the switch is way too sensitive. You just touch it and the circuit will... show more I have an existing third party module that is a black box. It runs on 12v car battery. Pressing a momentary switch causes the module to activate, playing the sound and flashing a number of LEDs in sequence.

The problem is that the switch is way too sensitive. You just touch it and the circuit will activate/deactivate. So to prevent accidental activation/deactivation what I want to do is add a delay circuit in front of the module such that you need to press and hold a momentary button for a few seconds before passing along a pulse to activate the black box module. If the button is released before the push and hold time passes no pulse should be passed along. The push and hold time does not to be very accurate, but should be in the range of 5-10 seconds.
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