One of the first lessons learned by anyone attempting to cook even a moderately complicated meal is do as much preparation as possible. The fewer steps which remain at runtime (as it were) the fewer the opportunities to poison guests.
As with cookery, so with hardware. Frequently-used subsystems, built and tested independently, are an invaluable aid to rapid prototyping. The picture above shows three:
- A power cable to carry +5v from the development board to the breadboard,
- A breakout board for a magnetic sensor, implementing the manufacturer's suggested circuit,
- An LED with 470R resistor in series (why don't manufacturers just sell these?)