To create partitions on a blank hard drive manually, choose “Specify partitions manually (advanced)”. The partitioner interface starts up with the “Prepare partitions” screen, listing any existing partitions. A graphical bar at the top will show the partition on your selected hard drive. For a blank hard drive, this will be empty. Your current hard disks and their partitions are listed in the main scrollable pane, with headings for Device, Type, Mount point, Format, Size, and Used space for each partition. For a blank hard drive, the hard drive is listed with a free space entry for the entire drive. At the bottom of the screen are actions you can perform on partitions and free space: New partition table, Add, Change, Delete, and Revert.
For a new blank hard drive, you first create the partition table, warning that it will erase any data on the drive. Click Continue. The warning dialog is there in case you accidentally click the New Partition Table button on a drive that has partitions you want to preserve. In this case, you can click Go Back and no new partition table is created.
You will have to create at least two partitions, one swap and the other a Linux partition where your system will be installed.
To create a new partition, select the free space entry for the hard disk and click the Add button. This opens a Create Partition dialog where you can choose the file system type (Use as) and the size of your partition. Do this for each partition.
The Create Partition dialog displays entries for the partition type (Primary or Logical), the size in megabytes, the location (beginning or end), the file system type (Use as), and the Mount point. For the partition type, the “Do not use” partition entry is initially selected. Choose a partition type from the drop-down menu. Select “Ext4 journaling file system” for the root partition and choose Swap for the swap partition.
The swap partition will have no mount point. You only set the size, normally to the amount of your computer’s RAM memory.
For the root partition, from the Mount point drop down menu choose the mount point /, which is the root directory. This is where your system will be installed. The size of the partition is specified in megabytes. It will be set to the remaining space. If you have not already set up the swap partition, reduce the size to allow space for the swap partition.
If you make a mistake, you can edit a partition by selecting it and clicking the Change button. This opens an Edit partitions window where you can make changes. You can also delete a partition, returning its space to free space, and then create a new one. Select the partition and click the Delete button. The partition is not actually deleted at this point. No changes are made at all until you start installing Ubuntu. The “Revert” button is always available to undo all the changes you specified so far, and start over from the original state of the hard disk.
When you have finished setting up your partitions, you will see entries for them displayed. The graphical bar at the top will show their size and location . Click the Install Now button to continue on to.