Oh, interesting, from a failed search for a different topic, I found this. With data from the analysis of the spatial layout of a room, you can 3D print the shape of an optimal reflector disk and cover that witn aluminum foil to improve Wi-Fi reception. This is cheaper than buying a directional Wi-Fi antenna.
Failed search.
20191219/DuckDuckGo how to open aluminum wireless charger
20191219/https://www.engadget.com/2017/11/08/research-aluminum-foil-improves-wifi/