Well for this I will show you the install for Microsoft Dos 6.22. Now follow the following steps.

1)  Start up your computer with the MSDos Disk 1 in the floppy drive

2) Boot up using the floppy drive

The following screen will now appear. Hit enter to continue.

You will now be prompted to configure the Hard Drive, this means it will be formated and all contents lost. Hit enter to continue.

You will be warned for the last time. Hit Y on the keyboard to continue..

You are now prompted that the system will restart, hit enter to continue and keep Disk 1 in the drive.