Which version of Data OnTap are you planning on using? There is an Install / Upgrade guide for each version. Also the System Admin and Storage Admin guides provide additional details for configuration.
The filer will start with a setup script that will handle some basics and get it online to the point where you can configure it via web page or ssh.
Each setup will be different depending on the purpose of the filer and the type of disks / networking / file access protocols that will be used.
In general, once the cabling is completed and the components power up with green lights,
run through the initial setup script
then you can change the networking to add vlan tagging or multi-level ifgrps (update /etc/rc)
secureadmin should already be enabled if the initial install is a version 8
configure the aggregate(s) as desired - may require moving vol0 around depending on how the initial aggr was configured during setup
configure vol0 - this volume's snap sched / snap reserve / language will be used as the default for all new volumes created.
add all licenses
verify fibre connectivity if needed
start up all file access protocols that will be needed
configure cifs, join AD if required
add local users for admin and other purposes
configure and test autosupport
change options as needed
update firmware on disks, shelves, rlm/sp, etc
test failover, test network redundancy, etc
document the filer and setup monitoring