When it comes to develop on SharePoint framework, you are free to use environment as your preference. It may be open source tool or proprietary. In the legacy models of SharePoint development, its highly coupled with the Visual Studio, but when it comes to this model you can use VS Code, Sublime, Brackets, Notepad++, Eclipse or any developer as you love most.
Following describes how to develop on SharePoint framework and you still like to develop with Visual Studio which is fully fledged development experience.
Step 1: Scaffolded your Office template to your dev folder. Reference: SharePoint Framework Scaffolding
Step 2: Install Node.js to to your Visual Studio. Following link for VS 2015 Community and search for your version of VS.
Step 3: Create new project as below
Step 4: Select where your node JS files are placed. This should be place where you have scaffolded office templates
Step 5: Select your startup file. This should be gulp file if you go with defaults nothing to change.