In words of Zig Zaggler - "Motivation doesn't last long, neither does bathing. Hence it is recommended everyday."
Now what can you do to keep your inner fizz high everyday?
I think you got to answer first "Are you doing something which you like? or Love?" IF NOT, then chances are nothing will keep you motivated.
Now if you are in something which you love, then following techniques might work:
1) Prioritize you work and finish in order of importance.
2) Finish the most difficult task first.
3) With every task completion your endorphin levels go high and you get a sense of achievement. Which in turn helps you to stay motivated to finish other tasks.
4) Don't be judgmental about people around you. Accept them the way they are.
5) Do not expect too much from yourself.
6) Healthy mind stays in healthy body. Dedicate at least half n hour of the day for well being of your body. Exercise daily.
7) Learn to let go! Even a second breath doesn't come unless you let the first go!
8) Develop some passion for a thing or two outside your work area. It could be sports, music, painting, writing, Anything. Follow you passion with rigor.
9) Be assertive than aggressive.
10) If you are stuck at something, don't keep spinning your wheels. Leave that task and move on to another. When your mind has rested, come back and try a new approach to the unfinished task.
11) Keep your mind filled with positive thoughts. Even in the darkest place, there's some light.
12) Keep plenty of friends. Whenever feeling down, pick up a phone and speak to 1 or 2 of them. That's a free way to get motivation.
13) Keep yourself away from the whiners!
14) Above all, the first person you should love should be "Yourself".
15) Write it and pin it on your board "SCREW IT, LET'S DO IT" - Richard Branson