To reduce 12V DC at 25 amps to 1V DC while increasing amperage, a buck DC-DC converter is recommended. This converter efficiently steps down voltage while allowing for a higher output current than the input current. The output current can be calculated using the formula, where power input equals power output, considering efficiency losses. Users are encouraged to explore tutorials on buck voltage regulators for detailed guidance. Understanding this technology is crucial for achieving the desired voltage and current transformation.