Leave it mixing long enough under a mixer to thoroughly wet the surfaces of all the particles.This is a powerful mixer that can put a lot of energy into the slurry and it only takes a few minutes for it to be silky smooth.
Do you really need to age clay when you make your own? No. In ancient Japan they did not have power blenders and propeller mixers, we do. To illustrate: I just sieved out the +80 mesh and +200 mesh particles from this raw clay (from one of our stockpiles) and then propeller-mixed it as a slurry. That wetted the particles very well and made it easy to sieve. Then I poured the slurry on to a clean plaster table and thirty minutes later it was ready-to-use. Slurry mixing is just as good as deairing in a pugmill. No wait! Particles wet even better. The plasticity of this clay is wonderful, and, it will not get much better with aging. Ancient Japanese potters used non-plastic, coarse particled clays so they needed to squeeze every last bit of plasticity out of them. Today, fine particled plastic clay materials are readily available. And we have bentonite, a few percent of that and any clay can be made super-plastic in minutes.
Slurry Mixing and Dewatering Your Own Clay Body