What we absolutely must know

1. What is my CPU. Identify it and make sure it's at least a quad core. TAKE A LOOK AT CPU-World
2. Check if the 'virtualization parameters' are enabled on BIOS using

LC_ALL=C lscpu | grep Virtualization

3. How much memory I have. Check the RAM and verify that is at least 4GB.
4. The amount of free space on my hard drive. The virtual machine can use a disk image file so extra partitions are not necessary.

Note

You can also use raw partition specific for virtual machines. See partitioning for more information

5. The minimum hardware requirements of the operating system you want to install as a virtual machine.