Do I need to submit all of the information on how the work was done (e.g. all Methods)?

A preprint should fairly and completely disclose the data and methods that are necessary to evaluate and replicate the work, just as in a journal publication. If properly performed, then authors should also receive credit and be properly cited for their discovery. As with the formatting question above, a more complete description will help a scientist to build a positive reputation for thorough and open scientific communication.