In order to make an Indian well you need to find saturated ground. Dig about half a metre down and wait for water to rise. But the first water is not good enough for you so skip that out. Then clearer water will come through. Let this settle for about 30min so everything murky will have gone to the bottom. Make sure when you skip the fresh water out you do not disturb the bottom.
If water doesn't flow well enough into the hole use a stick to poke the sides in.

Another thing you can do is dig on the beach when it is low tide. There will be fresh water as this is lighter that salt water. Make sure you don't dig too deep or else you will get to salty water again.

Also check for fresh water trickes in rock lines and holes in trees.

Reinhardt