I do very well in short projects or things that need to be done for a short term. But I procrastinate when I have very large projects or lengthy things to do. I kinda lack persistence. What is the best way to develop persistence? Also, if I know there is a possible outcome to the thing that I am doing, then I do that fast, I kinda like to dominate. But when I have things that are open ended I really struggle to move forward. Please advise.
One common answer to the question of "how do I keep making progress on a really big project" is to break it down into many smaller pieces. Depending on how you organize yourself, these smaller pieces could be viewed as subprojects, or tasks, or something else, but the trick is to make them really small. Forget milestones, think inch-pebbles instead.
You can help yourself plan that work by thinking backwards from completion. At the point where the Really Big Project is done, what is true in your world? Describe that to yourself, thoroughly and in detail. For example, "Thesis is complete. It is bound in a red leather binding, has 465 pages typeset in times new roman 12 point type, and sitting on the third shelf up at the right end. The title page looks like... and has a signature from my adviser showing it was approved... ". And so on. What had to be true for it to be bound in red leather? What had to be true to get 465 pages? What had to be true to get your thesis adviser to approve it?
Decompose the project in those terms, and you'll discover all kinds of pieces and parts to the project, each of which can be further broken down until you get to tasks of no more than a day or two in length. Once you're down to that level, it becomes very easy to see that you are making progress regularly against your goal.
Can you share you nature of work? Is it possible to break these large projects into number of smaller projects?
Actually you have the answer in your own question. Break big projects into smaller ones. If you can do that then you just have to care about completing each small project. Don't worry or stress yourself with the bigger picture. Plan a bit before starting off the big project. Divide it into smaller tasks or projects with milestones. On achieving each milestone, reward yourself.
Also with open-ended tasks, concentrate on the purpose, take the purpose and decay it into tasks.