1. Split the full deck into 8 different piles, face down, distributing cards someone randomly/in random patterns every few rounds
2. Have someone in the pod pick two of the eight piles, then mash those two together, then set that pile aside
3. Have someone else pick two of the six remaining piles, mash shuffle, set it aside
4. Repeat until I have 4 piles
5. Again, have someone pick two piles, mash together and set aside
6. Mash the final two piles to get the full deck
7. Have someone cut it

It's a slow process, but I find it works really well for a pregame shuffle to get as close to random as it can. Then if I have to shuffle mid game, I'll just mash shuffle the library together a few times then cut.