Add Dev setup to README

Author: VirxEC

README.md

@@ -10,6 +10,26 @@ A majority of the code is generated in the `codegen/` upon first compile and thr
 
 This includes the code generated by `flatc` (living in `src/generated`), the Python wrapper binds to the generated Rust code, and the Python type hints (`rlbot_flatbuffers.pyi`).
 
+### Dev setup
+
+- Ensure Python 3.11+ is installed
+- Create a virtual Python environment
+  - `python3 -m venv venv`
+- Activate the virtual environment
+  - Windows: `venv\Scripts\activate.bat`
+  - Linux: `source venv/bin/activate`
+- Install maturin
+  - `pip install maturin`
+- Build & install for testing
+  - `maturin develop --release`
+
+To use in another Python environment, like if testing [python-interface](https://github.com/VirxEC/python-interface/blob/master/README.md?plain=1), you can build the wheel:
+
+- `maturin build --release`
+- (In another environment) `pip install path/to/file.whl`
+
+The exact path of the wheel will be printed by maturin, just copy+paste it.
+
 ### Basic usage
 
 All classes and methods should have types hints readable by your IDE, removing the guesswork of common operations.