Cling film or petrolium jelly or both will protect the pan from your pm and will wash off nicely afterwards.  I don't know what a bunt pan is.  If it will be used for food afterwards I would definitely use plenty of cling wrap first.  Then possibly a layer of wet paper strips (no glue) before you add any further layers. 

To build up your height, it would really depend on what you need to achieve.  Personally for a solid structure I would build it up with balled up paper or pieces of cardboard then cover with paper strips and then possibly pulp. 

There are some great tips in the tutorials section and the forum on the site.  I also find checking out other peoples galleries a big help.

Hope this helps

Vicky