To answer this question we must take into account all aspects of the situation. It depends on the goals we are trying to accomplish, what it takes for your goal to come to fruition, the current state of the economy/world, and the current state of the qi we are working with.
For example, if you own a business and we are working to achieve an increased sales goal, it obviously takes some time for relationships to develop and deals to come through, particularly if the current state of qi is less favorable. It could take weeks to months. However, you will notice improved cooperation, more opportunities, channels opening up and/or easier progress along the way to your goal.
However, if your goal is to improve upon things that can shift faster, such as depression, some health aspects, relationship harmony, blockages in career, and more, you will often start noticing the effects of the strategies immediately.