I gap my plugs to the low side of spec, as the gap is always growing larger with wear.

This will make for a sligtly hotter & earlier spark, which can help on really cold winter starts.

I also use a little nickel anti-sieze on the plug threads & torque them to the Low side of spec, to allow for the antisieze acting as a thread lube, so I don't over torque them.

I butter on a light film of DowCorning, or GE dielectric grease inside the plug boots & onto the plugs external insulator, as this can help prevent flashover on those wet morning starts, or rainey days.
Use a clean non linty tool (no cotton swabs) to spread the dielectric grease inside the plug wires boots.

I use it on the coil end of the plug wires boot too.

If you have a distributor cap type ignition, you might have to use something like a hair pin under the wires boot to lift it a little to burp air out as you push it on the distributor cap & coil, or it can trap air & it'll act as a air spring that'll expand when warm & push the plug wire up put of the distributor cap or coil & cause a misfire.