I discovered the best method of soaking dried cuttlefish is using baking soda. A fast and common method used by many.
Soaking with plain water will only softened the dried cuttlefish but you will never achieve your desired expansion and softness.
One ball of baking soda.
One large container to fill the expanded cuttlefish
You can soak the dried cuttlefish until your desired tenderness and size but remember to change the water from time to time until the water becomes clear.
I have left the dried cuttlefish in the glass container for one day.
Here is the end results.
Rinse thoroughly and drained.
If you do not wish to cook immediately, stored them in Lock & Lock containers and freeze them.
Check out these links on how I prepared the pre-soaked cuttlefish recipes.