You have probably already signed messages with your BTC address. This is almost the same here!

You just have to imagine:
Public key = your BTC address
Secret key = Private key of your BTC address

Go to the site: https://tweetnacl.js.org/#/sign

1. click on 'random' and write down the secret key and the public key (remember the secret key is like your private key at BTC. Your future key for further tasks, so that you do not have to create a new one each time)

2. write in the Message field (without spaces front or back). OgKBFR13cfSEMKG4dhU2p0q4MIOW1Oi6NAKbV3LtnrB5HR2MCoUSjsDy9xDMzw6YyR71cTfRzKlRVcq ia1vSUQ==

3. click Sign (you don't need the Secret key anymore for this task after this point), then a Signature should appear (just like BTC)

4. you write this Signature in the Evaluation Statement at 'Signature of hash' (marked red):

Then just insert your public key (from step 1) (marked green)

---

Public Key:

Claim Identifier: 26HCsa7MldWXjplJMd6Js++bitjDw+ILhkQ1rn9/2R+6DVmh/EX43vEYIrYzppabv8DKy5OSglHwPYq4GbPIwg==
Full Property Name: Zenoribbon of Rainbow Road
Abbreviations: ZR, Zenoribbon
I searched the internet for a few minutes and was unable to find any earlier homestead claim to any similar works as named or abbreviated "Zenoribbon", though ZR is too generic of a term to search and so ignored.
I honor this homestead claim as an original creation.
Hash of the above evaluation statement: OgKBFR13cfSEMKG4dhU2p0q4MIOW1Oi6NAKbV3LtnrB5HR2MCoUSjsDy9xDMzw6YyR71cTfRzKlRVcq ia1vSUQ==
Signature (of hash):

That should take care of the whole thing, I think!