Document various tips to iterate faster when building & deploying WSL (#14146)

Author: OneBlue

doc/docs/dev-loop.md

@@ -72,3 +72,32 @@ See [debugging](debugging.md) for general debugging instructions.
 
 To attach a debugger to the unit test process, use: `/waitfordebugger` when calling `test.bat`. 
 Use `/breakonfailure` to automatically break on the first test failure. 
+
+## Tips and tricks
+
+**Building and deploying faster** 
+
+To iterate faster, create a copy of [```UserConfig.cmake.sample```](https://github.com/microsoft/WSL/blob/master/UserConfig.cmake.sample):
+
+```
+copy UserConfig.cmake.sample UserConfig.cmake
+```
+
+And uncomment this line:
+
+```
+# set(WSL_DEV_BINARY_PATH "C:/wsldev")
+```
+
+This will change the build logic to build a smaller package that installs faster.
+Also see:
+
+- `WSL_BUILD_THIN_PACKAGE` to build an even smaller package
+- `WSL_POST_BUILD_COMMAND` to automatically deploy the package during build
+
+**Code formatting**
+
+Every pull request needs to be clang-formatted before it can be merged.
+
+The code can be manually formatted by running: `powershell .\FormatSource.ps1 -ModifiedOnly $false`.
+To automatically check formatting when creating a commit, run: `tools\SetupClangFormat.bat`