How to solder:

Step 1: Turn on soldering iron and wait for it to heat up.

Step 2: Wipe of soldering iron with moist sponge.

Step 3: Wrap the wires together and secure them.

Step 4: Put one end of the solder to the wire and then put the soldering iron on the opposite side

Step 5: Wait for solder to melt onto wire.

Step 6: Clean up properly

This is related to engineering because you need to solder many things when building objects and connecting wires.