Add more Git instructions

notes-and-examples/2026.06.12/overview.md

@@ -1,12 +1,21 @@
 ## Outline
 
 - Write a red-black tree with rebalancing
-- Assignment: finish the red-black tree
+- Assignment: start on the red-black tree
+    - Requirement: you must use the left- and right-rotation code in the previous assignment
+    - You may change the code to fit the class
 - Next week: introduce graphs and graph algorithms
 
 ## Git reference
 
-Add all new files and changes to your code:
+There are two repositories to keep track of:
+
+- [My code](https://gitea.bchen.dev/brendan/dsa-tutoring)
+  - Get notes and sample code
+- [Your code](https://gitea.bchen.dev/ethan/dsa-homework)
+  - Submit your homework
+
+To submit homework, add all new files and changes to your code:
 
 ```
 git add .
@@ -23,3 +32,10 @@ Push changes:
 ```
 git push
 ```
+
+
+To pull new changes to the notes and sample code, run this in the `dsa-tutoring` directory:
+
+```
+git pull
+```