Update 'WINDOWS_INSTALL.md'

WINDOWS_INSTALL.md

@@ -33,3 +33,16 @@ you will end with a project like this.
 2. Go to project settings and add the libs project to your own as shown in the picture
 
 ![pycharm new project screen](./docs/img/img_4.png)
+
+3. Add your first file to your project and click in install requirements to automatically download all the dependencies
+
+4. When all the dependencies are satistied, we are good to go to start importing our first model.
+
+by adding the following code to our main.py
+
+```
+from geometry.geometry_factory import GeometryFactory
+
+city = GeometryFactory('citygml', 'myfile.gml').city
+
+```