Electronic statements
Many banks and creditcard companies offer the option of changing your paper statements to digital statements. These can be mailed to you, or downloaded from the bank's website.
Automatic payment of bills
Just think about how many bills you get each month. Most companies won't mind if you ask them to automate your payments. It saves them time, it saves you time and it reduces paper consumption.
Scan and recycle incoming documents
Anything else you receive each month can be scanned into your pc and then recycled. Watch out for legal documents, for instance the deed to your house. You need to keep the original of these documents for them to stay legal.
Stop taking notes on paper
I used to take notes on a large notepad, which would lead to consuming aproxomatly 300 sheets of paper a month. Now I use all my gadgets to take notes. By using a tool like Microsoft's OneNote or Evernote you can take notes on your PC, laptop and mobile phone. All of these notes can be synchronized so you have all of the notes in one place.