SharePoint Framework - Starting a new project

1. Setup your development environment based on the steps defined at https://dev.office.com/sharepoint/docs/spfx/set-up-your-development-environment

2. At command prompt use following command - 

yo @microsoft/sharepoint

3. Install the developer certificate for use with SPFx development, switch to your console, make sure you are still in your project directory and enter the following command:

gulp trust-dev-cert

4. Enter the following command in the console to build and preview your web part:

gulp serve