Everyone is going to answer this a little bit differently depending on preferences, but let me answer this question based on what scripting means to ME, for my personal manifesting practice.
In loose terms, scripting manifesting is when you sit down and write a SCRIPT that describes in detail the reality you are trying to manifest. You might want to do this in the form of a “Dear Universe letter,” which is when you write a letter to the universe, stating that you are so grateful and thankful for the new reality you are experiencing. Personally, I write something like “Dear Universe, I am so thankful and grateful, now that I _______________, and then I fill in the blank with as much detail as I can think of (this can go on for five or six pages, depending on how much thought I have given to the scenario I am trying to bring about). I then use the script to come up with a really powerful “I am” affirmation (for example: “I am a bestselling author!”), which I then take right into the 5 X 55 technique and write that down every single day, 55 times a day for 5 days. That is just my personal practice, but you can just write the script and stop there, or you can go further and combine the script with any of the other cool manifesting practices out there, like 333, 369, or 11:11, whatever speaks to you.
I use this journal to do that, but you can totally just use a notebook. By writing out the script in detail, you connect with the emotions of already having that experience. This makes it MUCH easier to picture the scenario in your mind when you are writing your affirmations every single day. In a way, scripting is a written form of visualization, because you see it in your mind before you write it all down.
This will work great for you if you are the kind of person who loves physically writing things down. Personally, I don’t like the standard “visualization” of law of attraction practices that much, because I am too ADHD to sit still and picture something, and I end up feeling like I am forcing it. I much prefer these written affirmation techniques because they give me something to actually DO while I’m sitting there, which I find makes it much easier for me to get “into the flow” and picture that thing. Remember, you’re trying to hold that thought for at least 17 seconds so that it will begin to take shape!