Just to show that there are often many “correct” solutions, the clock/flip-flop above is really just implementing a square-wave, so it could be simplified:
The True at the top is a tweak-boolean representing your button & the watch at the bottom represents the LED so I can test in simulation mode (simulation cannot simulate physical hardware like buttons & LEDs).
One advantage of this solution, is there are other wave nodes that could be used instead if you want the flashing to fade on/off.
I suppose if you wanted to, you could even use tri-wave and use the different steps of the wave to represent multiple values. There will be fewer nodes than using count with compare/defer nodes to reset, but it would be more convoluted/obfuscated (harder to understand what you are doing), and timing issues might cause rounding errors that cause specific values to get skipped sometimes.