There are multiple ways to achieve this operation. First, cast a circle around your area of focus. Instructions on creating an 18-VSF or 21-VSF are located following this description.
Envision a neutral 5 point pentagram field, then duplicate it, and rotate the second one slightly while focusing on one point. Once it is 1/3 of the way to the next point in the original pentagram field, duplicate it again, and move the third pentagram field to a position exactly between the 1st and 2nd fields. You now have three evenly spaced pentagrams, creating a 15 point pentakaidecagram.
Once you have established the 15 point pentakaidecagram field, envision each point being activated with a color in the spectrum. Begin at one point with red, then skip to yellow for the next point in the circle, then green, blue, and purple, then back to red and continue all the way around the circle. You will end with three of each color: red, yellow, green, blue, purple. This will give you a 15 point vibrational spectral field (15-VSF).
A second way to achieve this is to simply envision triangles of each of the 5 colors listed above in the spectrum. For different spectral properties and effects, choose a color other than orange to omit, but have caution when experimenting in this way! Start with one color, then move to the next, establishing each triangle slightly rotated from the first triangle you generate (exactly 1/5 of the way to the next point in that original colored triangle). You may have to adjust your visual matrix slightly after placing all five colored triangles, to ensure cohesion, even spacing, and a tightly structured vibrational field.
When unable to spend the time generating the field from scratch, one can also almost instantly establish this field when already in a high-energy state. Simply connect to the horizontal disk of energy around the Throat Chakra, and spread it to the edge of the circle you are establishing. This will automatically establish a 15 point vibrational spectral field (15-VSF) when your Throat Chakra is clear, balanced, and energized. Keep in mind that the field generated in this way will exactly reflect the state of your Throat Chakra, so do not trust that it will be effective when you have a sore-throat, or are experiencing other communication issues!
Finally, visualize this field beginning to spin, and watch as the colors blur together until you have a field of brilliant white light surrounding you. Notice the original 15 point pentakaidecagram is still visible, but now every point appears to be a full rainbow.
Extend your attention upward and downward from your center to a certain distance above and below you. Notice that the spectral field will expand as you move your attention, keeping a full envelope of light around the area of your conscious attention. This is an effective way to sort, identify, and absorb ANY energy entering your field or directed at you. External energy entering will illuminate a color in your spectral field more prominently as the energy is absorbed. Dark energy, vampiric hooks, or congested control cables will immediately splinter into their component vibrations and be harmlessly absorbed and add energy to your field.
This operation can also be completed to create a 18 point octakaidecagram, or 21 point icosakaidecagram field by beginning with a 6 point hexagram field for the former (18-VSF, adding orange when activating the spectrum) , or beginning with a 7 point heptagram field for the latter (21-VSF, adding orange between R/Y and a white-light point between P/R) .