> Keep lines to the crystal very short
Minimize radiated noise levels

>Put a 7V Transzorb across the power
A varistor of sorts, helps absorb power spikes exceeding 7V

>Feed the Vcc through a schottky diode - and put
>2x 10uf (low ESR) and 4x .1uf on the PIC side.
I think this is just for filtering the power supply. The 10uF take care of the lower frequency noise and the 0.1uF take care of the high frequency noise

>Use an LF part (so that it will run at a lower voltage)
Run it at 4MHz
Consumes less power and I believe generates less noise


>put 2K in series with every input along with a .1uF to GND right at the chip.
Limits the input current and filters high frequencies

>If possible, put a 330 ohm resistor in series with every output.
Prevents over-driving the outputs

I think he was just going over the entire setup that he does when be builds something. Every little bit helps that is for certain. If I made an error in my assessment please correct me as I too need to continue learning new things.