First, you need to have an Alby account, if you don't already. Alby is invite only, so you'll need to find someone with a spare invite code.

Next, you'll need to get Alby Hub installed on your Start9. A video guide can be found here: https://guides.getalby.com/user-guide/v/alby-account-and-browser-extension/alby-hub/alby-hub-flavors/umbrel-start9-etc

Next, you will need to connect your Alby Hub to your Alby account. This can be done by either giving Alby Hub access to your entire node balance, which is fine if you are the only one who needs to use your node's liquidity, or you can set up an "isolated" wallet connection, that keeps track of its balance separately from your node's full balance. Whichever you choose, copy and paste the full connection string into your Alby account when it asks you to connect a wallet.

Finally, you will want to set up NWC from your Alby account to Nostr clients you use, like #Amethyst. Go to the "Connect" tab on your web dashboard in your Alby account, and then click on NWC Connections and "+ Connect App." Give your new connection a name and a monthly budged, click next, and then copy paste the connection string to whatever Nostr client you use.

This should get you set up with one-tap-zaps in your Nostr client, and you will just need to put your Alby lightning address into your profile to start receiving zaps to your node.

Thought I did. Still figuring it out 😅