Take a tiny piece of jeggery (GUD.) every hour. Just keep it in the mouth and slowly suck it till acidity subsides.
Drink coconut water 3-4 times a day. Have a plateful of watermelon (tarbuch) and/or cucumber (kheera) every hour.
Harade juice, 1-2 teaspoon daily after meals is very effective in controlling acidity. The juice can be mixed with an equal amount of amla juice for better results. To take out amla juice , grate an amla and squeeze the pulp through a clean muslin cloth to get juice.
Chewing a piece of harad is an age old remedy.