Registering new Nebula U passport from your mate's invitation link is first considered. Both you and the invitee can get 10% extra crystals.
You can also register with the invitation code
EXTRA10%CRYSTALS or the invitation link by yourself. In this case, you still can get the 10% extra crystals.
After register, be sure to validate your email, then move to the next step.
Download the client from here. Only 64bit host system is supported. It is recommended to install the client on Windows 10 or Windows 11.
Generate the API key from here, then copy to somewhere.
Login the client with your name and API key. Attention, neither the email nor password will be use in the client.
Login the client with you name and API key.
Start New Task button, and wait for the task completed.
Now you have explored a new planet successfully.
Once you login the client, crystals start being exploited. Keep your planets online as you can.
The more planets, the more crystals.
Invite your mates to join in Nebula U, you will get extra crystals from them constantly.