Add a separate /home after installation?

[Jon N <jdnandroid@gmail.com>]

Hi,

When I installed Debian I put everything in one partition.  Now I'm
wondering what I was thinking.  / is ext4 for mated on a drive with
eufi partition table, no raid or lvm.  My thought is if I can shrink
that and create a new partition I can copy over /home and then mount
it as /home.

I am pretty sure it can be shrunk, although I guess I'll have boot
from another disk (it can't be shrunk while mounted I would guess).
Does this sound like a reasonable way to do this?

Thanks,
Jon