Q: I want to delete my current I.cloud account and sign up with a new one

Go to Settings>iCloud, tap Delete Account and provide the password when prompted (if running iOS 7).  Then sign back in with a different ID to create your new account.  Be sure to save any photo stream photos you wish to keep to your camera roll before deleting the account by opening your my photo stream album, tapping Select, tapping the photos, tap the share icon (box with upward facing arrow, then tapping Save to Camera Roll.

If you want to migrate your data to the new account, you'll need to open each of your notes and email them to yourself so you can later copy and paste the text into new notes created in your new account.  Then go to Settings>iCloud, tap Delete Account, choose Keep on My iPad and provide the password when prompted.  Then sign back in with a different Apple ID to create your new account and choose Merge to upload your data.