If you have device which is supported by the Plasma Mobile, you can help by flashing edge rootfs, and testing out and reporting bugs.
There are some bugs where we could really do with help reproducing it as well testing.
- Plasma Discover shows undefined entries in Settings menu: https://bugs.kde.org/399647 ... This specific bug is heisenbug and maintainer of the Discover is unable to reproduce it.
In addition to this, you can help by testing out general shell functions.