Debian 9.8 Post-Installation Steps on VirtualBox (GNOME)

Enable auto-login

• Settings > Users > Unlock
• Automatic Login ON

Disable screen lock

• Settings > Privacy > Screen Lock
• Automatic Screen Lock OFF

Install guest additions

• (VirtualBox) Devices > Insert Guest Additions CD Image…

•  su
   apt install linux-headers-$(uname -r) gcc make perl
   mkdir GuestAdditions
   cp -rf /mnt/cdrom/* GuestAdditions/
   cd GuestAdditions
   ./VBoxLinuxAdditions.run
  

Set up sudo

su
apt install sudo
usermod -aG sudo username

Add user to the VirtualBox share folders group

sudo usermod -aG vboxsf