When I do most of the things that I do day to day, it's important for me to have a reason to do it. I need to know why am I doing the thing that I'm doing. My importance for it is that I need to know my options and if I can discover a more efficient or pleasant approach, I will experiment.
My readings about rituals and spells have not shown me much reason to follow the instructions and without that, the act seems trivial. Part of this is from my belief and very novice level of understanding of magick in general. In short, I believe that magick is internal energy (for each of us) that is directed as desired.
I'll use the Relaxation Ritual as an example. This has shown up in my research several times, each with in depth instruction. I have performed it for the sake of following instruction. I have not seen a reason given for it other than to relax. In my mind, the other reason would be to practice focusing on energy manipulation.
The Golden Ball of Light starting below the feet (as it's described from one source) immediately falls outside of my idea that the energy I'm working with is internal. The energy focus part of it seems unnatural for me.
However, I feel my energy in a white aura originating from my chest and expanding, almost like an inflatable costume. My focus is much more defined. As I continue with my own version of the ritual, I am relaxed and I'm working the energy in a controlled manner.
So, let's take this further. My questions to all comers is what is the importance of following instructions for rituals and spells? How much does intent come into play? How does a belief affect results?
I feel that there is no strong emphasis placed on how close one follows the instructions for any given exercise and spell.
Exercises are good, but will not work the same for everyone, and some may experience no results at all, which is where experimentation, trial and error come into play. If it doesn't work, change and tweak it, and keep doing so until you get the combination that works best for you.
As for spells, I feel that the practitioner themselves should create them. Or at the very least, find a spell that matches their intent, and shred it, change it, tweak it, until they have made it their own and no longer resembles anything of the previous spell.
Intent and belief are everything in magick, and one of the things I find essential. It is what drives their working to manifest (among other things) and if it is not present and directed, then ittle result, if any, will be made to manifest.
Instructions especially the ones found in books, like Modern Magick, are like general recipes. They offer insight into how to perform a ritual which has a certain effect, but in realisty these can be stripped down. For example a recipe for red sauce may involve red wine, but you may not like it, so you will omit it or substitute it. So long as there are tomatoes in there the base remains the same. The same is true for the relaxation exercise- you can simply choose a different centre from which to emanate the energy from so long at the intention is the same there will be no issue.
I think yoga nidra is one of the best relaxation practices out there, and all it requires is breathing and cycling the consciousness through each body part in turn and consciously releasing all tension. That is all that golden ball of light is really in the relaxation ritual- your consciousness, it doesn't come from an outside source per se, it manifests from within you- your mind.
I don't think thereis aone-size-fits-all magic spell, ritual, or magical working. Magic is, by its nature, varied in its application and extremely subjective to the person using it.
I believe that any and all written spells, rituals, and outlines (even meditations) are simply basic guidelines which give suggestions or ideas to the reader on how to proceed, and not, in fact, directions meant to be followed precisely.
For those people who can realize the value in using self-created methodology and processes for their own personal workings, it is generally acknowledged to be more effective to create and follow their own methods, rather than trying to first translate, then follow, these directions.
However, for more inexperienced practitioners, the guidance received from them mayprove to be an invaluable way to open their minds, thoughts, and ideas; as well as become the catalyst or a sort of precursor to the creation of their own spells and etc.
So just strive to do what feels best and most correct to you!