Update README.md

Author: hangzhaomit

README.md

@@ -104,6 +104,11 @@ The code is developed under the following configurations.
 
 *Warning:* We don't support the outdated Python 2 anymore. PyTorch 0.4.0 or higher is required to run the codes.
 
+As PyTorch 0.4.0 is not officially released yet. We suggest running in a separate conda environment, and install the following PyTorch package:
+```bash
+conda install -c prigoyal pytorch=0.4.0
+```
+
 ## Quick start: Test on an image using our trained model 
 1. Here is a simple demo to do inference on a single image:
 ```bash