The lz4 compression algorithm is fast enough to be used by default, even for incompressible data.

zfs set compress=on						zroot

Create a Boot Environment hierarchy

zfs create -o mountpoint=none					zroot/ROOT
zfs create -o mountpoint=none					zroot/ROOT/default
mount -t zfs zroot/ROOT/default /mnt

Create the rest of the filesystems.

zfs create -o mountpoint=/tmp	-o exec=on	-o setuid=off	zroot/tmp
zfs create -o canmount=off -o mountpoint=/usr			zroot/usr
zfs create							zroot/usr/home
zfs create 			-o exec=off	-o setuid=off	zroot/usr/src
zfs create 							zroot/usr/obj
zfs create -o mountpoint=/usr/ports		-o setuid=off	zroot/usr/ports
zfs create 			-o exec=off	-o setuid=off	zroot/usr/ports/distfiles
zfs create 			-o exec=off	-o setuid=off	zroot/usr/ports/packages
zfs create -o canmount=off -o mountpoint=/var			zroot/var
zfs create 			-o exec=off	-o setuid=off	zroot/var/audit
zfs create 			-o exec=off	-o setuid=off	zroot/var/crash
zfs create 			-o exec=off	-o setuid=off	zroot/var/log
zfs create -o atime=on		-o exec=off	-o setuid=off	zroot/var/mail
zfs create 			-o exec=on	-o setuid=off	zroot/var/tmp

Links and Permissions

ln -s /usr/home /mnt/home
chmod 1777 /mnt/var/tmp
chmod 1777 /mnt/tmp