Pre seed accuracy

I'm thinking about buying pre seed in the next week or so before my fertile window and I had a few questions before I do. When do you use it? Like every time you have sex or just on your most fertile day? Tell me your story and your results of any! I have seen a lot of women saying it works the first time using it so I really wanna give it a go! Tell me everything and anything about it!  Please and thank you!!