So while Installing Incus , during initilization, there is a way to make sure that all the profiles, volumes, images and containers can be stored in a seperate drive. In this case, I'm using a spare 500GB Samsung 850 SATA III SSD. And I'm planning on using BTRFS for my file system.

Here is how I went through it:

All Commands in this post are intended to executed as a non-root user on the host machine

Prerequisites

Install BTRFS related packages:

sudo apt install btrfs-progs -y 

Identifing the Drive

Find the Device ID using:

Terminal

lsblk

Output:

NAME          MAJ:MIN RM   SIZE RO TYPE  MOUNTPOINTS
sda             8:0    0 931.5G  0 disk  
└─sda1          8:1    0 931.5G  0 part  
sdb             8:16   0 465.8G  0 disk  /var/lib/incus/storage-pools/incus_500
zram0         251:0    0    16G  0 disk  [SWAP]
nvme0n1       259:0    0   1.8T  0 disk  
├─nvme0n1p1   259:1    0   100M  0 part  
├─nvme0n1p2   259:2    0    16M  0 part  
├─nvme0n1p3   259:3    0   1.8T  0 part  
└─nvme0n1p4   259:4    0   768M  0 part  
nvme1n1       259:5    0   1.8T  0 disk  
├─nvme1n1p1   259:6    0  1022M  0 part  /boot/efi
├─nvme1n1p2   259:7    0     4G  0 part  /recovery
├─nvme1n1p3   259:8    0   1.8T  0 part  /
└─nvme1n1p4   259:9    0     4G  0 part  
  └─cryptswap 252:0    0     4G  0 crypt [SWAP]

In this case my intended device is /dev/sdb as its the only drive corresponding to my 500GB drive. If Unsure, Try the GUI method below:

GUI (Recommended)

I use Pop_OS! for my host machine and it ships with gnome-disks but another popular application would be gparted

In case they are not currently installed in your machine, you can them as follows:

Gnome Disks:

sudo apt install gnome-disks -y

GParted:

sudo apt install gparted -y

Format the Drive:

Terminal

The TL:DR

sudo parted /dev/sdb mklabel gpt
sudo parted -a optimal /dev/sdb mkpart primary btrfs 0% 100%
sudo mkfs.btrfs -f /dev/sdb1

A Deeper Explaination:

Create a New GPT Partition table:

sudo parted /dev/sdb mklabel gpt

Create a New Partition (using all available space):

sudo parted -a optimal /dev/sdb mkpart primary btrfs 0% 100%

Format the partition as BTRFS:

sudo mkfs.btrfs -f /dev/sdb1

GUI

DIsks:

Empty Block (Terminal Only)

sudo dd if=/dev/zero of=/dev/sdb bs=4M count=10