Add release instructions

Author: simolus3

README.md

@@ -1,6 +1,21 @@
 [SQLite](https://sqlite.org/index.html) and [SQLite3MultipleCiphers](https://github.com/utelle/SQLite3MultipleCiphers),
 packaged for the Swift package manager.
 
+## Releasing
+
+This package is consumed by our Swift SDK with a SwiftPM git dependency.
+By convention, we release this package after updating SQLite and creating a tag named after the SQLite version
+(e.g. `3.51.2`, without a `v` prefix).
+
+The easiest way to release this package is to create a release and tag on GitHub, with a description linking
+to the SQLite and SQLite3 Multiple Ciphers sources:
+
+```
+This release mirrors [SQLite 3.51.2](https://sqlite.org/releaselog/3_51_2.html) and [SQLite3MultipleCiphers 2.2.7](https://github.com/utelle/SQLite3MultipleCiphers/releases/tag/v2.2.7).
+```
+
+No further pre-release checks or builds are required for this package.
+
 ## Acknowledgements
 
 This project was heavily inspired by [@sbooth's work](https://github.com/sbooth/CSQLite/tree/main).