First of all, make sure you have Node.js installed in a newer version than 0.10.
Open cmd, exec: node -v
If it’s not the right one, go to node.js page and get the latest .msi for Windows.
You are going to need to install Python 2.7, just get the installer from Python’s download page and follow the steps. To make your life easier, you will need to add python as an environment variable, you can do this manually or check the option “Add python.exe to path” at the “Customize install” screen during the installation: select “Will be installed on local harddrive”.
Restart your cmd command window (close and open, changes on environment variables may not be effective if not).
Note: You may need to restart your computer at this point, but you can try to move to next step.
Just execute: npm install protractor -g
Webdriver-manager is already installed with protractor, but you still need to execute: webdriver-manager update
You may not need to install this one as protractor seems to install its core but if you find trouble just exec: npm install jasmine -g