How to change order boot (GRUB)

Two months ago, Debian 8 was installed on my desktop. This means my desktop has two operating systems: Windows 7 and Debian 8. By default, Debian 8 boots at start. But how can Windows 7 boots at start? All you have to do is follow the next steps:

  1. sudo nano /etc/default/grub;
  2. pick index (0..n)
  3. edit order Default=0 to Default=2 which means Debian 8 no longer is booting at start but Windows 7!
  4. sudo update-grub

Source: How to change the boot order of a dual-boot Linux PC