Identify your goal: creaminess (sauces), milk solids (batter/body), or sweetness (only if the recipe is sweet).
Choose the closest match from the table (evaporated milk for creamy body; strained Greek yogurt for thickness; buttermilk/kefir for liquid with acidity).
Use the listed ratio for your milk powder amount, then adjust consistency by adding water/milk in small spoonfuls.
If your swap is thicker than milk powder reconstitution (yogurt or coconut cream), thin it first to match your batter/sauce thickness.
Re-check after 2–3 minutes of cooking or mixing: milk powder mainly changes body, so small liquid tweaks matter.