Oh man, I struggled with this A LOT.
I found out that using the Pomodoro thecnique helped me a great deal, having 20 minutes of really focused work, knowing I have a little bit of rest afterwards was a good motivator. I used ClearFocus for that, it's a simple and beatiful android app that helps you apply the pomodoro thecnique.
However, although Pomodoro is great when you know what needs to be done and have clear objectives, I still had a problem with the bigger picture: I needed someway to keep a list of objectives and tasks that needed to be done. For that particular matter I implemented an Scrum board at my workplace, and I higly recommend doing so.
It's very simple. grab a large cardboard, and draw 3 columns on it:
To Do,
In Progress and
Completed. Put all that needs to be done on sticky notes. Each sticky note should be a few words and symbolize a focused unit of work: "Clean up desk", "call Steve about accounting" "Research campaign emails" that should last you no more than two hours, this way you are forced to split your sticky notes and get more granularity.
Then you can only have one post it at once in your "In Progress" column. So pick one from the To Do and move to progress. Once you are done with that note, move it to "Completed". Rinse and repeat. There are apps you can use to make this like Trello but I personally better with a real, physical board, although your experience might differ
You can even set up different colored sticky notes to mean something different, like priority or even categorize your tasks.
