Mounting
Mounting devices is an everyday part of the maintenance of a Linux system.
This guide is not recommended for #newbies as the slightest error will prevent your system from booting.
If you are new to Linux or less experienced the recommended way is to use systemd mount units. Such units will - in case of errors - not render your system unbootable. Instead use this guide - much safer - systemwise.
If you are comfortable with editing your fstab and otherwise proficient in *nix administration - please continue
Using terminal
Locate your device name and partition
lsblk -o PATH,SIZE,HOTPLUG,MODEL
If will be something like /dev/sdy1 - setup a variable - replace sdy1 with your actual partition
PARTITION=/dev/sdy1
Create a variable with the path (no spaces) where you want to mount the partition (outside the home folder)
MOUNTPOINT=/data/mydevice
Create the mountpoint
sudo mkdir -p ${MOUNTPOINT}
Set permissions on mount point
sudo chmod ugo+rwx ${MOUNTPOINT}
Create a merge file - in case the device is not present at boot time we set some mount options
nofail noauto device-timeout automount. man systemd mount (5)
echo "UUID=$(lsblk -no UUID ${PARTITION}) ${MOUNTPOINT} $(lsblk -no FSTYPE ${PARTITION}) rw,noatime,nofail,auto,x-systemd.automount,x-systemd.device-timeout=1ms 0 2" > automount.txt
Verify content (example)
❯ cat automount.txt
UUID=1f3d1a6e-b4b5-46da-909a-8a87a45dd18b /data/mydevice ext4 rw,noatime,nofail,auto,x-systemd.automount,x-systemd.device-timeout=1ms 0 2
Merge with your fstab
sudo cat automount.txt >> /etc/fstab
Mount the partition
sudo mount -a
You can of course create a script - add it to your toolbox - e.g. add-mount.sh and make it executable chmod +x add-mount.sh
#!/bin/bash
if [[ $(whoami) != "root" ]]; then
echo "Please run as root!"
exit
fi
PARTITION=$1
MOUNTPOINT=$2
if [[ -z ${PARTITION} ]]; then
echo "Partition empty -> exit"
exit 1
fi
if [[ -z ${MOUNTPOINT} ]]; then
echo "Mountpoint empty -> exit"
exit 1
fi
sudo mkdir -p ${MOUNTPOINT}
sudo chmod ugo+rwx ${MOUNTPOINT}
echo "UUID=$(lsblk -no UUID ${PARTITION}) ${MOUNTPOINT} $(lsblk -no FSTYPE ${PARTITION}) rw,noatime,nofail,auto,x-systemd.automount,x-systemd.device-timeout=1ms 0 2" > ~/automount.txt
echo "..."
echo "Adding line to fstab"
cat ~/automount.txt
sudo cat ~/automount.txt >> /etc/fstab
sudo mount -a
Use it like this
./add-mount.sh /dev/sdy1 /data/my-device
And yes - you can use Gnome Disks - but where the fun in that 
