Signal Flow in Schematics

When you look at a schematic, signal flow is left to right.

When you draw a schematic, use this convention. Also, arrange positive voltages at the top and ground (or negative voltages) at the bottom, so you can think of current flow down the page.

Above is a digital schematic. Since any wire might be an input or output, or even a bidirectional signal, it is hard to decide where the signals are flowing. The blue notes point out some signs of inputs and outputs.

Above is an analog schematic. The signal flow is in yellow, from left to right. The blue arrows might be a signal flow. The XLR jack is used mainly for balanced signals.