Installing linux on ROG GL552VW (Beginner)

I carried out a fresh install of 16.04 on my ASUS GL552VW.

The only additional GRUB parameters I entered (for installation and normal boot) were:

nouveau.modeset=0

To stop Nouveau from taking over.

Once I'd installed the nVidia 361.42 drivers, through the Additional Drivers tab in Software Updater, I had to disable Secure Boot. (Secure boot stops unsigned kernel modules loading)

With those settings, everything works. Touchpad, Skylake support, nVidia graphics @ 1920x1080, Wifi, Bluetooth, keyboard backlight.

Installation of 16.04 is much less hassle than previous versions.

Bumblebee is deprecated, likely the guide you were following is outdated, the Nvidia drivers come with everything you need to manage your multi GPU laptop.

First remove any installed driver and Bumblebee

sudo apt-get purge bumblebee nvidia*

Now reboot

sudo reboot

Now install the latest Nvidia driver from the repository (if you can't reboot to Ubuntu use recovery mode)

sudo apt-get install nvidia-352

This includes nvidia-prime that you can use to control your GPU's, you can find it in the application nvidia-settings.

"how can I check if the whole system works correctly?"

As you mean check what drivers are in use, you can check the application additional drivers, this is preinstalled in Ubuntu Gnome.