The day you stop needing the recipe is the day you’re allowed to start changing it.

Improvising requires knowing what the rules are for. Follow the method exactly a few times and you learn what each step is doing, which is the only thing that lets you tell a good deviation from a mistake. Change things before that and you cannot interpret the result, because you do not know what was supposed to happen.

So make it exactly as written three times before you touch anything. Then alter one variable, once, and taste the difference. That is also how you get to argue with a coach, a teacher or a style, and be worth listening to.