There are many kinds of staff. To be each one, there is a requirement, and you might need to already be a staff member.
To Become a Global Mod, you have to be a mod, and be able to moderate just about every forum.
To become a reporter, you need to be a webkinz or up. They make sure everything is going Ok on WF, telling staff about anything.
Graphic Staff need to have a shop in the Avatar section, and/or have made excellent graphics before. It is possible you could be chosen before the 'webkinz' stages. Otherwise, you must be a webkinz, Signature webkinz or other staff member. You will be making graphics for the site.
To be a Webkinz Trainer, you have to be a Signature Webkinz or another kind of staff. You need to be excellent in the Webkinz Forums. You will train the lil' kinz.
To become a Mod, you either need to be an excellent Signature Webkinz or webkinz trainer.
To become a Global Mod, you must be a mod and earn the position, you can edit every forum.
To become a Future Admin, you have to be a global mod, and sign up. (and be accepted)
To become an Administrator, you have to be a future founder, and can edit the WF admin panel
To become a Founder, you need to be a future founder, and you could get accepted.
You cannot become a Bot. They are for staff to use.
I hope this helps you out!