Well the one thing dad never taught me was electrical stuff.
I have a Kicker LED marine speaker to put in. The LED connector has red, green, blue, and black wires. I cut the connector off and stripped the wires.
Now I have to put a different connector on. This connector has red, green, black, and yellow wires.
Red to red. Green to green. Fine.
For the rest, Blue to black, or blue to yellow?