1. Try  Little Office Yoga: If you are feeling rather lazy or slow, try a little office yoga. Sit, back straight with your palms face up on the table. Close your eyes and breathe in deeply. Then curl and uncurl your fingers one after the other while breathing deeply. This would help clear your mind and focus on the tasks ahead. Block everything out during the period of this yoga which should take about 5 - 10 minutes. Afterwards, delve full swing into the work like you've missed it for days.
2. Use Productivity Software: By now, you have gathered momentum and are in the thick of things. In order not to lose your steam, trying using productivity tools which would boost your output. Google Chrome store offers some apps that make working effortless and fun. Try some apps, from Mindmeister for mind mapping, Transcribe for transcription and a host of others. If you can think of it then its probably somewhere on this earth. Search for and find a software that would aid your eventual output.
3. Kill The Fear Factor with Positive reinforcement: Don't give in to the thought that you cannot do your work or that your work isn't good enough. tell yourself positive things that would starve the feeling of fear and inadequacy. If possible, listen to audio message that would put your mind in the right place.
4. Feed Your Brain....and self: You will achieve absolutely nothing if your stomach is empty. You need to put something in your stomach so that your body id ready for the mental task that its going to be involved in. Fruits are an amazing example of foods that would help you rather than distract you from the work at hand.
You also need to feed your brain. Read when you are tired or less busy so you are more enlightned than you were a few moments ago.
5. Build Your Self Discipline: Avoid distractions, give yourself deadlines. Mentally you challenge yourself to become better than where you are currently.
That said, go on and have a super productive day.