Amazon s3 with Carrierwave

Hello G.s ,
i am using Rails 3.0.3 with carrierwave gem and i have use amazon s3 ,
so guys can you please tell me what are the various configurations
that need to be done and how we can check which users have uploaded
which files or images like i want to check the images which are
uploaded by corresponding user. And when a user logged in my rails app
those images should be shown. I have checked the link but still have
some confusions help me regarding this issue.

thanks
nishant