How does a neuron know to which one of the next neurons to pass the signal
The neuron that sends the signal does not know which neuron to send the info to. The job of the neurons getting the signal is to identify whether it is their turn to get activated by the signal. 

This is controlled by a protein. Depending on how often the neuron is used, a number of channels are formed on the surface of the dendrites. The activation happens at an optimal level of the protein present in the cell depending on the number of channels on the surface.. Each time the cell receives the signal, this some of this protein is created. 

First, the neurons with most channels is activated, but if the organism does not get the memory that is wants, the earlier neuron will continue with sending more signals. Then receiving-neuron-number-1 stops activating (because peak concentration has passed) and the next one starts. This continues for all neurons. 

In layman's terms, from info-1 to info-2, info-2 is chosen in the order of thoughts most associated with info-1 to least associated.