I choose Debian as a platform for gns3 which will contain virtual network elements of block 1 mentioned before. So, start with getting the most recent net install version; debian-7.3.0-amd64-netinst.iso (in my case) from http://www.debian.org/distrib/
I will start with creating a new virtual machine in my WMWare Player. If you decide to use VMWare Player also, it may be obtained from https://my.vmware.com/web/vmware/free#desktop_end_user_computing/vmware_player/6_0 which should be fine for personal use. To create a new virtual machine, just choose the “Create a New Virtual Machine” tab and browse to the iso file of your preferred os.
Select Linux as operating system and choose the most appropriate version (debian 6 in my case), then give a virtual machine name and a physical location on hard drive, selecting an hard disk size a bit greater than recomended will not give harm;
What I will do next is custumizing hardware with setting memory to 1GB and adding 3 host-only network adapters. These adaptors will enable gns3 to connect router interfaces to peripheral systems later.
Next will be responding to installation dialogs of debian, and mostly choosing next, next next. Hopefully within an hour, system should be ready for installing gns3 which is my main target. What will follow is setting gns3 with some network elements in it…