Quote by Lee Haney goes like this "Exercise to stimulate, not to annihilate. The world wasn't formed in a day, and neither were we. Set small goals and build upon them."

If you want to achieve something that is big, something that you have never done before then there is nothing wrong with it at all. All you have to understand that the 1st step is one of the most important ones. You have to understand the fact that it is better to walk if you can't run. It is better to give yourself some extra time so that you can build a good base. Too much rush will drain you out soon. So the best strategy is to do what you are capable of doing today. Do not burn yourself out in one go. Instead take small, steady steps continuously and keep moving ahead.