Vinegar is the preferred method for cleaning a shower head because its acidity naturally dissolves built-up limescale without the use of harsh chemicals.
Step 1: Fill Bag With Vinegar
Step 2: Put the Bag Over Shower Head
Step 3: Fasten With a Rubber Band
Step 4: Soak for Several Hours
Step 5: Remove
Step 6: Run Hot Water
Step 7: Unclog Nozzles With Toothpick
Step 8: Polish With Cloth
And now your shower head is clean.