Как подключить правильно Browsersync к готовому gulipfile?

var gulp = require('gulp'),
	sass = require('gulp-sass'),
	autoprefixer = require('gulp-autoprefixer'),
	cleanCSS = require('gulp-clean-css'),
	pug = require('gulp-pug'),
	concat = require('gulp-concat'),
	uglyfly = require('gulp-uglyfly'),
	imagemin = require('gulp-imagemin');

var browserSync = require('browser-sync').create();

gulp.task('sass',function() {
	return gulp.src(['./src/sass/**/*.sass','sass/**/*.scss'])
		.pipe(sass({outputStyle:'expanded'}).on('error',sass.logError))
		.pipe(autoprefixer('last 2 versions'))
		.pipe(cleanCSS())
		.pipe(gulp.dest('./dist/css'));
});

gulp.task('html', function buildHTML(){
	return gulp.src('./src/pug/**/*.pug')
		.pipe(pug({ pretty: true }))
		.pipe(gulp.dest('./dist/html'));
});

gulp.task('js', function(){
	return gulp.src(['./src/js/jquery-3.2.1.min.js', './src/js/bundle.js'])
		.pipe(concat('bundle.js'))
		.pipe(uglyfly())
		.pipe(gulp.dest('./dist/js'));
});

gulp.task('imagemin', function () {
	return gulp.src('./src/images/**/*')
		.pipe(imagemin())
		.pipe(gulp.dest('./dist/images'));
});

gulp.task('assets', function () {
	return gulp.src('./src/assets/**/*')
		.pipe(gulp.dest('./dist/assets'));
});

gulp.task('watch', function(){
	gulp.watch(['./src/sass/**/*.sass','./src/sass/**/*.scss'],['sass']);
	gulp.watch(['./src/pug/**/*.pug'],['html']);
	gulp.watch(['./src/js/*.js'],['js']);
	gulp.watch(['./src/assets/**/*'],['assets']);
	//gulp.watch(['./src/images/**/*'],['imagemin']);
});

gulp.task('default', ['sass', 'html', 'js', 'assets', 'watch']);