It is actually as easy as creating a /swap partition with Gparted (or using the Live install media) and then adding it to your /etc/fstab.
1/ Create the partition, right click it and 'swapon' so it is active;
2/ Open a terminal and:
There, you should see an entry something like this, probably last line. The important part is it ends with "swap"
Take note of the UUID number (in bold above, yours will be different). Now, open the /etc/fstab file:
/dev/zram0: UUID="e197b72d-b267-4572-82f2-1c259f4ab79c" TYPE="swap"
... and add this at the very end:
sudo nano /etc/fstab
... replacing the UUID with the UUID number you found for "swap" in the 'sudo blkid' command. But the number ONLY. Don't included the " at either end like 'sudo blkid' output does.
UUID=e197b72d-b267-4572-82f2-1c259f4ab79c none swap sw 0 0
Reboot and you have a swap partition. 2Gb /swap is fine or same as your installed RAM if you hibernate. Good luck.