Here is what the Evasion website suggests -
-Backup your iOS device using iTunes or iCloud before using evasi0n. This way you are sure to never lose any data if something wrong happens.
-Please disable the lock passcode of your iOS device before using evasi0n. It can cause issues.
-Be patient while the jailbreaking process is running, don’t start iTunes or Xcode in the meanwhile. The best is to not touch the computer until the end of the jailbreaking process.
What can you do at the moment? Get your devices ready for the jailbreak as it could be out at any instant. We’ll be sure to notify as soon as the update goes live.