Installing onto a USB stick for a home server advice?

[Moltke]

So I'm retiring my old server, a HP DL380 G4 with Windows Server 2012, at my home.

I bought a used dell poweredge R330 w/ xeon 1270 v5 and 16GB of ECC ram for dirt cheap since the casing was damaged on the back but does not impact the server at all.  It only has 4x 3.5 sas hotswap bays on the front.  No big deal.  Very quiet 1u server, a rarity.

I updated all bios and firmware for ALL hardware, including the power supplies firmware.

It does have one internal usb port though and instead of wasting the 4x 6TB SAS3 drives I have, why not throw the OS onto a 64GB USB stick I have laying around.

Any advice on installing the OS onto the USB stick?  Things I should do or not do?

It is possible. Just install it like you would in a HDD. You'll need to burn the .iso either to a USB or a DVD, boot the system from that device and install it onto your 64GB stick. I have a couple of distros installed that way and they work just fine. Persistence would be good but then you wont be able to update the kernel when/if you need/want to, at least not in an easy way.