Fully hydrated panels should weigh about 1lb. The surface should be slick and moist. White optical distortions in the corners of the cells indicates full hydration.
For Rapid Hydration
*or if your water has a mineral content
Just:
Remove Mylar panels from packaging
Completely submerge in Hot water.
Hold under water and scrunch out any air.
Continue manipulating cells until they are full.(panels should weigh about 1lb)
Squeeze excess water from cells. (but Not All water)