Most of us who already work 40hrs a week cannot work any harder (that’s a lie but you need to fit family, hobby and the rest of it in somewhere). I’d say you need to be more focused. Focus in my experience can boost productivity 2 to 3 times. It is easier said than done but there are several strategies available to you:
1. To-do List: I use this a lot. It helps me to focus on what is the most important thing right now.
2. Notepad: A notepad can be used to draw diagrams, gather thoughts and keeping progress. If you find that you often get interrupted and find it difficult to get back to what you were doing before, this can help you out by jotting down where you are up to before you jump to something else.
3. Take regular digression: You cannot totally focus without a bit of lax in between. It also helps ease the pressure built up in eyes and other parts of the body. I would opt for getting out of my desk, perhaps take a walk or make a drink, etc.
4. Find and eliminate sources of distraction: If you are sitting at a windows seat and you can’t stop perving at people walking by, pull down the blind when you need to. If it is the background gossip that you can’t get away from get a headphone. Hunt down those source of distraction and improve your focus.
5. Gauge your progress: If you can tell by some metrics that by being more focused you are more productive than it does ease the adjusting pain.
The above are what I find most helpful to me, but you may have a bit of get-ahead of your own. Feel free to share them in the comments.