Using these connectors is a breeze. First, if you're working in an SMT line, simply paste over the through holes and the pads will solder in place. When connecting to Qwiic boards and cables, just match the pins with the corresponding colored wires. The red wire is for 3.3VDC power, the black is for ground, the blue is for I2C SDA data, and the yellow is for I2C SCL clock. Since the cables are symmetric, you don't have to worry about which side goes where. As for maintenance, keep them in a dry place to avoid any corrosion. If you need more details about JST SH connectors, check out the JST website.