A sigil, a wish, a manifestation, a dream, a proclamation, a goal, a mission, should be written in it’s purest form. Write it down and ask why you want it. Write the answer down and ask why you want that, and so on. You will come to a point where you cannot easily answer anymore. When trying to answer draws only unintelligible mumbling sounds from you, you have reached your limit. This may happen at different levels depending on the individual. We are all different after all. Regardless, once you have purified your statement of intent as much as you can, it will be pure enough to be easily focussed since your own perception is instrumental in the process. It just has to be as pure as YOU can make it.