Add document about using lldbclient.py

Bug: 185210505
Test: manual
Change-Id: I9407fd478a32b3068a4c1fae1e0ae9041864c01d
diff --git a/microdroid/README.md b/microdroid/README.md
index 5cfa523..3523e9d 100644
--- a/microdroid/README.md
+++ b/microdroid/README.md
@@ -171,3 +171,17 @@
 ```
 
 Done. Now you are logged into Microdroid. Have fun!
+
+Once you have an adb connection with `vm_shell`, `localhost:8000` will be the
+serial of microdroid.
+
+## Debugging the payload on microdroid
+
+Like a normal adb device, you can debug native processes using `lldbclient.py`
+script, either by running a new process, or attaching to an existing process.
+Use `vm_shell` tool above, and then run `lldbclient.py`.
+
+```sh
+development/scripts/lldbclient.py -s localhost:8000 --chroot . --user '' \
+    (-p PID | -n NAME | -r ...)
+```