High ceilings are good! Carpets generally are not!
First you have to set out your goals. Soundproofing (preferably referred to as isolation) is extremely expensive and requires great deals of Mass and airtight sealing, and is thus usually out of the question for most except professionals with large budgets.
Most require only room treatment, as for many, the room in question is simply being adapted and very often is also a bedroom, rather than being built for purpose.
Decide too what your purpose is, the requirements for a recording studio are much different than a control room or mixing studio. For many of us we need to do all of the above in a single room - a so called Project Studio - in which case you may run accross the term “live end dead end” among others.
The answer to your question regarding paper is no - similarly forget any notions you may have heard regarding egg cartons!
There are numerous types of treatment from absorbers through traps and resonaters to diffusors. The absorber treatment is usually the most common. Being the cheapest and easiest to build, they are ideal for those on a restricted budget. Absorber panels when hung horizontally from the coeling are called clouds. The diffusor category should only be considered if you have a large space at your disposal.
First thing to do is make a ground plan of the room with accurate measurements, and then use one of the many room mode calculators to give you an idea of the frequencies that are going to be problematic and where. The plan may also help in working out reflection vectors.
Next decide upon orientation. Usually you’ll want the audio firing down the length of the room as opposed to across the width. Decide upon your Listening position and test this position with your ears or using a room profiling software (I recommend REW as it’s very effective, and FREE Optoma | Home Theater Forum and Systems)
and then consider the best position for your treatments.
For information and examples etc. visit John L. Sayers Forum John Sayers' Recording Studio Design Forum • Index page and also Gearslutz http://www.gearslutz.com/board/studio-building-acoustics/, also check out the articles on http://realtraps.com/ and http://gikacoustics.com/.