I try to install express package using npm from inside /home/iwan/my-project directory:
npm install express express@3.3.7 ../node_modules/express ├── method
You could also create a blank package.json file using guidelines from the https://docs.npmjs.com/files/package.json webpage. Then place this in your project folder and type npm install.
https://docs.npmjs.com/files/package.json
npm install