Orient the diode so that its cathode is connected toward the incoming power (5V supply) while the anode faces the intersection with the switch.
This reverse connection is intended to block current flow when the switch is open and allow current flow when the switch is closed.
Wire the Components Together
Draw a net from the 5V DC power supply output that splits into two branches:
One branch goes to the input of the SPST switch.
The second branch goes directly to the reverse-biased 1N4148 diode.
Connect the output from the SPST switch such that, when closed, it allows current to flow through the diode.
Connect the Common Ground
Ensure that the negative terminal of the 5V DC power supply and any other necessary parts of the circuit share a common GND symbol.
Connect the ground nets appropriately across the schematic.
These instructions will establish a basic switch-diode configuration in the PCB schematic, ensuring that the switch permits current flow through the diode when closed, while the diode blocks current when the switch is open.