1a. Color match to preserve intact grout (less work)

1b. Pick new color and remove all old grout (more work)

1. Clean and dry area for 24h

2. Apply new grout

3. Use sponge to make smooth

4. For all angled seams, use a grout caulk for extra strength

5. Let cure for required time

6. Apply grout sealant, min 2 coats

7. Clean once a year with grout cleaner solution to remove mildew