How do I get a private key and certificate for a release?

[sven]

The user @universityofgames posted a great guide on the forums how to do just that:

How to convert Unity Keystore to PK8 format?

Hello, When your team is porting game to another engine / technology, it will always encounter some difficulty. One of them is certification. As you can guess, not all game engines / applications use the same certificate format. In our scenario, Unity Game Engine use *.keystore format, but Defold Engine require *.PK8 and *.PEM. How to extract it from the *.keystore file? Before we start we need to get the tools below: (a) OpenSSL’s homepage and OpenSSL (b) KeyStore Explorer Once you’ve inst…

I bet there are a bunch of other guides available online as well.