Step 3: Only one direction
Step 5: Switches
Step 6: Trimpot
Step 7: Power Regulator
Step 8: Socket to me
Step 9: What Next?
For the 2x16 Blue display, use a 28 Ohm resistor (Red Gray Black).
For the 4x20 Blue display, use a 33 Ohm resistor (Orange Orange Black)
Place this resistor in the spot marked Rbl.
Step 10: The headers
Solder in the pins at each end and then check for alignment before soldering the remaining pins.