diff --git a/readme.txt b/readme.txt
index 83fa3bb..6be3800 100644
--- a/readme.txt
+++ b/readme.txt
@@ -6,15 +6,35 @@ The default door.py use ipython kernel to create a ipython env. You can remote c
 
 Debug version could not run.
 
-BUILD AND RUN
+Prepare and Build
 - Install python. And pip install ipython, ipykernel, jupyter-console.
+  - Choose 32 bit or 64 bit python same as the process that you want to inject.
+  - The ipython, ipykernel, jupyter-console is not necessary, but if you want to use the default door.py, you should install it. 
 - Modify python.props.
+  - Modify the path string C:\Python37-32 and C:\Python37 to your python install location. 
+  - If you only want 32bit version, ignore x64 path.
 - Build the solution.
-- Copy pythonXX.dll to Release folder.
-- Edit door.py for your own. 
+
+Usage
 - Copy pydoor.dll, pythonXX.dll, some vc runtime dlls and door.py to the diretory same with host process image file.
 - Find a way to inject pydoor.dll to the host process.
+- Dbgview.exe (You can found in Sysinternals Suite) can view log message.
 
 NOTE
 - The debug version could not running most cases, because don't have debug binaries for some python modules.
 
+About default door.py
+
+The default door.py start an embedded ipython kernel. When you successfully injected dll, you can run command `ipython console --existing` to connect pydoor.
+
+> The ipython environment created by `IPython.embed_kernel()` is very strange, has some variable scoping issue ...
+
+
+中文简介
+
+简单说，这个 dll 就是用来注入到别的进程，会创建新的线程并运行同目录下的 door.py 。
+
+后记：这个 pydoor 个人一直觉得比较鸡肋，感觉没啥用，直到……
+
+
+