Some more details to the rebase instructions

README.md

@@ -4,14 +4,16 @@ Following Jorge Castro's lead and making my own spin on Silverblue
 
 ## Rebasing onto this image
 
-From another Silverblue based image, first, rebase onto the unsigned image.
+This bootstrapping process helps get the public keys onto your machine 
+and makes sure everything is configured right. 
+
+From another Silverblue based image, first, rebase onto the _unverified_ image.
 
 ```
 rpm-ostree rebase ostree-unverified-registry:ghcr.io/samhclark/custom-silverblue:41
 ```
 
-Optional: Verify that the image you just rebased onto is signed.
-
+Optional: Manually verify that the image you just rebased onto is signed.
 
 ```
 $ wget -O - https://raw.githubusercontent.com/samhclark/custom-silverblue/refs/heads/main/overlay-root/usr/etc/pki/cosign/cosign.pub \
@@ -22,10 +24,14 @@ $ wget -O - https://raw.githubusercontent.com/samhclark/custom-silverblue/refs/h
     )
 ```
 
-Reboot.
-Then, after that, rebase onto the signed image. 
-This bootstrapping process helps get the public keys onto your machine 
-and makes sure everything is configured right. 
+If the above command fails (returns with a non-zero exit code), then you should abort the rebase
+
+```
+rpm-ostree cleanup --pending
+```
+
+Assuming it succeeded, then reboot: `systemctl reboot`.
+After that, rebase onto the signed image. 
 
 ```
 rpm-ostree rebase ostree-image-signed:docker://ghcr.io/samhclark/custom-silverblue:41