Step 1: First, run a magnet over the dry mixture. Iron filings stick to the magnet and are removed (magnetic separation). Step 2: Add water to the remaining sand and salt and stir. Salt dissolves, but sand does not. Step 3: Filter the mixture. Sand stays on the filter paper (residue) and salt solution passes through (filtrate). Step 4: Heat the filtrate to evaporate the water. Solid salt is left behind. Step 5: The magnet must be used before adding water, because wet iron would rust and mix with the sand. Answer: Magnet → add water and filter → evaporate the filtrate.