Anyone can start mining using the GUI wallet. Links to download the wallet:

Please update to last wallet version and remove old blocks from UltraNote folder or connect to a remote node from top menu Settings > Connection
On our Wiki you can find information about how you can replace your blocks

https://wiki.ultranote.org/faq.html

Windows GUI Wallet: https://ultranote.org/UltraNoteWallet-1.0.27-beta-win64.zip
sha256: 012bcbc91c5f24aa48bed35ec78a5cfc0b4de7759d716478457c759e1ad6fa9f

Linux GUI Wallet: https://ultranote.org/UltraNoteWallet-1.0.27-beta.amd64.deb
Sha256: 01a8e8d2c3fa308d43ccb39fd432ec8d836a38c6f95b5c721c19de037d746c58

Mac GUI Wallet: https://ultranote.org/UltraNoteWallet-1.0.27-beta.dmg
Sha256: dd66789d83fead86b414200f66ce0502601788736e8950a2761408f6d4b11c4e