To 'enchant' an object is to fill it with energy for a particular purpose. Although there are all kinds of "spooky-ookey" ritualized and dramatic ways to do this, all that is essentially the energy is directly programmed that was assembled and shaped by the will of a magician with a deliberate visualization. What happens in the mind is a microcosm of what happens in the macrocosm of the physical world. This is what the phrase "as above, so below" means. What happens in the microcosm of our mind can be directly reflected in the macrocosm of the world outside the mind.
So, to enchant an object and turn it into a talisman, all you have to do is to direct energy to focus on a particular goal and point in the object. In the case of being "invisible" what you want to do is see walking along in a swirl of fog hiding (the haze represents the energy that you collect.) Do you mind to see people beginning to see the fog, only to have the view "slide" off, pulled to one side or attracted by something near you, rather than focusing on you. Once you have built a clear picture of what in your mind then view the ring and watch mists of the energy being sucked up and stored in the ring or whatever object you fancy.
When all vapors are developed in the ring is completed... Maybe. At this point, you can "seal" the ring and do with it, or you can add a "trigger", which in turn, the power of the talisman or voluntarily.
With the first, the Medallion is constantly active and the only way to stop this is to remove it and place it in a bag or something that was directly responsible for blocking the activity of the track.
The latter, which you are installing on/off switch at the bottom. This may be a set of words and phrases (make sure it is something easy to remember, but not so common, that they are used in everyday language: "shields up" and "shields down" works well) or you can use a view simple (if you want to enable, visualize the fog, leaving the ring and around you, and when you want to remove the ring the fog is pulled back into the ring.)
Creating a trigger takes a little more from you, but usually worth it, as you can always wear the ring with confidence. With the other method, you must consciously put it on and take it off, which increases the risk of losing the ring... and some things are harder to find, than the invisibility talisman!
I would also like to point out that while the ritual itself seems on the surface to be quite large, it could be easily resolved and adjusted to your personal preferences The cleaning of the ring or any magickal item for that matter can be done simply by running it in clear water, while visualizing all unwanted energies being washed into sewers.
MY WAY OF ENCHANTING OBJECTS.
Runes will be drawn on a sheet of white paper with ink of your color Zodiac (if possible write them in a circular pattern, put the ring or object inside the circle of runes), and then do either Chants, Prayers, or what I do: send energy through my hands to it.
The key to this, or any type of magic is that you have a clear and stable "image" Thy will be done ... what we want to happen. This is what is to allow the subconscious to gather the energies of the program/enchantment you need and want to use. If you are not sure * exactly * what you want to achieve these results would be uncertain. You do not need to know the exact mechanics of "how" to perform (in fact, it is usually the best, if only to set some basic parameters, and let the universe take care of the details), but you must know and understand exactly "what" and "why."
An amulet, however, is a natural object (ie, crystals, stones, plants, feathers, of course (shedded) etc., which have some "virtues" and the magical properties as an inherent part of their existence .