Hi, essentially what I need to do is create a 555 monostable circuit but instead of the push button, I need the circuit to run continuously. For example 2 sec on, 2 sec off, 2 sec on, 2 sec off... etc. etc.

My circuit has an LED, a switch button and a lead off to another LED (which is toggled by the same button). I know I can flicker the LED with ease, however, i need to do this for the whole circuit such that the button can only toggle the LED when the primary LED is lit. A basic representation of what I need is attached.

 

Then use the 555 in astable mode, select the resistor /capacitor values to suit your flashing rate.

 

Here is a 555 astable calculator