Laying a power cable and an optical cable typically involves digging a trench, carefully placing the cables within it, ensuring proper spacing between them, and then covering the trench with soil, often with additional protective measures like warning tape to mark the cable location; this process can be done through direct burial or by using protective conduits depending on the environment and project requirements, with the key difference being that power cables usually need a shallower trench compared to optical cables due to their different heat dissipation needs.