update README

README.md

@@ -5,4 +5,33 @@
 Use the following command to serve the website locally:
 ```bash
 docker run -it --rm --network=host -v $(pwd):/site kashu98/jekyll-serve
-```
+```
+
+## For Future Instructors
+
+Create a new branch for each semester as `website<year><semester>` (e.g., `website2024fa`, `website2025sp`, etc.)., and update the content accordingly.
+
+
+### Where to Update
+- Announcements: `_announcements/*.md`
+- Assignments: `_assignments/*.md`
+- Lectures: `_lectures/*.md`
+- Events: `_events/*.md`
+- People: `_data/people.yml`
+
+
+### Archive Previous Semester's Website
+
+Create a directory `archive` to store the previous semester's website.
+Inside the `archive` directory, put the generated `_site` directory from the previous semester's website as `<year><semester>`.
+
+- Note that when generating the `_site` directory for each year, make sure to remove archive directory to avoid recursive copying.
+- Relative path in the `archive` might be broken, so make sure to update the path accordingly.
+- Should we automate this process with GitHub Actions?
+    - create a deploy branch
+    - mkdir archive
+    - for each branch in the repo
+        - jekyll build
+        - replace all the relative path in _site
+        - move _site to archive/<year><semester>
+    - build the current website