There are very few policies which apply across all Wikia. These can be found on the Central Wikia at Wikia:Category:Policy.
Other policies for this Wikia should be decided by the wiki community. It's generally best to keep policies as simple as possible, and not to introduce too many rules. A growing wiki can usually do well with a few simple policies and a lot of goodwill and cooperation.
[[Category:Policy]] to any policy pages will add them to the policy category. This is found here.
See also World of Goo Wiki:Simplified ruleset