projectSetup

Open terminal => CTRL+ALT+T

Make a folder for your project

1. mkdir project
2. cd project

3. npm init
=> fill out all the needed stuff; name, description, whatever

4. npm i -D gulp gulp-sass
=> waiting

5. make two folders, one for your source code, one for your 'built' code that gulp creates
=> /project
  - build
  - src
  
6. goto src folder and make index.html and css folder

7. In terminal: touch gulpfile.js => creates a gulpfile.js

8. open gulpfile.js with whatever text-editor. For example: atom gulpfile.js

9. Inside
var gulp = require('gulp');
var sass = require('gulp-sass');

// compiles sass to css and copies it into build/css folder
gulp.task('styles', function() {
  gulp.src('./src/css/*.sass')
    .pipe(sass())
    .pipe(gulp.dest('./build');
});

// copies index.html from src to build
gulp.task('html', function(){
  gulp.src('./src/index.html)
    .pipe(gulp.dest('./build');
});