Actually we all have that problem when we are beginning to take the drawing more seriously.
Not for nothing it is easier to imitate and copy, but creating something new in our mind is difficult and complicated
Of course, one that you manage to create that idea will be a million times more satisfying than achieving a replica of an image.
I know very well to frustrate you that the drawing does not come out as you imagined it, that is one of the reasons why I share these guides with you, when you know all these drawing techniques and tools very well, you will be able to draw exactly how You imagine it and even better ^ _ ^.