What gets measured gets done - Management Maxim

Write a list of what you want to do on a physical piece of paper, listing each item line by line.

If an item on the list seems too overwhelming to do, break it down into smaller parts.

It's okay, even encouraged, to put down easy tasks on the list. If I want to do a software project, often the first item on my list is something like "start Eclipse". If you just complete the first thing on the list, next thing you know you'll be knocking down the entire thing.

For cleaning your room, you should write down a really easy task as your first task. Something like "bring the cleaning supplies out of the closet" or "move all my clothes into the hamper" that should take only a few minutes (if even!).

Post the list on the wall with some tape. After you complete each item on the list, check it off. If you find your self too lazy to do that, write down "get tape" and "post list on the wall" as your first two tasks and check each off as you complete them.

This is the best trick I have by far for getting myself to do work, I can't think of a time where I wanted to do something and failed to do it after breaking it down on a to do list.

A lot of the problem is psychological - as is the answer. If you answer these questions, it may help you understand why you are procrastinating:

• What am I afraid of?
• What will happen if I stop procrastinating on this project?
• What will (ultimately) happen if I procrastinate on this project?
• What am I using to avoid doing what I should be doing?

Note that sometimes we can do things that need doing in order to avoid other things that need doing more urgently.

Doing the following will help you to stop procrastinating:

• Do one small thing. Cleaning a room? Forget the room: do one corner, or just one counter. You may find that you want to keep going - that's the idea!
• Don't look at the big picture: concentrate on that one small thing.
• Set a repeating five minute timer: if you have shifted from your main focus after five minutes, then refocus onto the main goal.
• Set a timer for a different reason: after 15 or 20 minutes, quit and do something else: a reward of sorts.
• Get some help: it's harder to get distracted if someone is there to help you maintain focus.
• Break down your goals into smaller goals - even daily goals. With small goals, you can do one each day and find that you are making progress on the big goals.
• Change your habits: add habits one by one to help you maintain your desired goals: e.g, putting clothes away each night, or doing laundry daily (if need be), or keeping that spot clear (the one which always seems to get messy fast).

Try using GTD: it can help if you focus on doing the tasks and following through.

Usually I write a schedule of what I'm gonna do the next day. It helps me getting into things because it feels like somebody else already took the decision for me (my past self), and it's easier for him to plan something for somebody else (your future self). Of course it doesn't forces you to actually do the things and you can always find a mental excuse to avoid following the schedule.
But so far it have yielded good results for me, and it's easy to give it a try.
This may not treat the root cause of your procrastination, but I believe it can prove to be effective to get yourself started/engaged, then think about why you're always choosing instant gratification over long term commitment once you see that you are able to achieve what you want in small steps.

Good answers here already - I have just one thing to add.

What ultimately helped me move past procrastination was serious meditation on where procrastination left me. I focused on specific times when procrastination truly impacted my life negatively, and worked to remap the procrastination impulse.

What I mean by this is the following: when the experience the specific impulse to defer a task to later, we are doing this because some lower part of our mind has weighed the value of a free "now" against the discounted value of a free "later". If this is a rational deferral, we don't call it procrastination, so it is by definition an irrational one, i.e., one where the value of the free now turned out to be less than the free later.

Self-awareness, i.e., awareness of the moment in which you're experiencing the impulse is key. Once you can do that, you can say to yourself: "In the past when I felt this impulse, and I engaged it and procrastinated, it resulted in pain later on. Maybe I should do it RIGHT THIS SECOND."

A key insight I gained from this process was that it wasn't the entirety of the task that I was dreading - it was just getting started.

To add to the "very" useful advice of @sskates , I would say that even when you find yourself doing "one particular" task for many hours, you might end up procrastinating. Reason: You are bored.

My advice is, when you make a "plan" for tomorrow, do make sure that you include the things of an entirely "different" task too, in your schedule. This way if ever you feel bored with one task, you'll always have something else to do (to refresh your mind).

Also, I think rewarding yourself with some perks may also help in the required motivation. Example: If your "weakness" are video games, write in the chart that after I complete 5 tasks, I'll be playing a game for half an hour.

In my house, you will find post it notes on my creativity room. They are categorized into three.

To Do. Where I put everything I have to do within a day first. I cannot do everything, but I must place what I felt I must do so that I will not forget them.

Doing Then I will transfer six of the post it notes to the under doing. I write the amount of time I needed for each activity.

DONE When every thing is done, then it is a great time to congratulate yourself. Doing this, you will see that many things are getting done.

Above my To Do, Doing, and Done notes are the following words: DO IT NOW.