I recently installed Ubuntu to use both my hard drive (HDD) and solid-state drive (SSD). There are many different approaches to this, and below I'm going to detail how I setup mine. I have my operating system installed on the SSD and all my data on the HDD.
First, I installed Ubuntu normally, solely on the SSD. No need to do advanced configuration during the installation. The installer will allow you to choose the disk to install the operating system on. If you need help installing, I suggest looking at this guide.
Next, I booted up my new operating system, and created one huge
ext4 partition on my hard drive using GParted.
Choose your hard-drive in the upper right hand corner dropdown. Delete all current partitions by right-clicking on them and choosing "delete". Next, create a new partition by right-clicking on the unallocated space and choosing "New". All your documents will be stored on this, so make the partition as large as possible. The file system should be
After you click create, click the checkmark in the menu to apply all operations.
Almost done. Launch the Disks manager and choose your hard-drive from the left-hand menu. Click on your newly-created partition, then click on the settings gear below it and open up the "Edit Mount Options" dialog.
In the modal window, set "Mount at startup" to true and "Mount Point" to
\home. Click OK, then reboot your computer. To double-check that everything is working, open up the file manager and view your hard drive. Your home directory should be on that disk. Congratulations!