This is a neat and reasonably easy way to replace the standard Honda relay with one that is switched on by the kill switch instead of the ignition unit. First you need a relay, I use automotive relays as they are easy to get hold of and fit the original relay holder.
I always solder crimping plugs when used on a bike as vibration can cause the crimp to come loose, I then insulate them with heat shrink. Honda use standard automotive cable connections so I use a three pin connector to make it as neat as possible and means it can be put back to standard in seconds if required. I also use a piggyback crimp on the live to the coils to provide the switched live so no damage is done to original wiring.
On this relay the 12v goes to pins 1 and 2 the switched live for the pump goes to 3 and 5. The neutral or earth connects to the frame earth under the seat and the 12v positive goes to the black and white wire on the coils.
If you don’t want to use the original connectors then you can cut the insulation back on the black and the white cables on the three pin relay plug and solder your cables to them instead. Any questions just ask.