You vibrate Rune A first, then Rune B second, then Rune C third and so forth till your done and then program and direct.
So R + R + R etc.etc.
I recall a recent member mentioning an interesting theory. That Sowilo should be vibrated last. Because one of the actions Sowilo does is increase the power of other runes. Their understanding is Sowilo should pump up the radiation of the previous runes. It's not wrong to use the rune beginning, middle, or end. But this person did point out an interesting alternative to Sowilo's usage.
Funny it's kinda like pre-heating. You can pre-program with affirmation to set the "tone" of the working. And after working with the energy raising, program the energy and direct. Most people seem to prefer to fire off the energy and THEN program. Kinda like how some people like to program, raise energy, program, raise more energy, program etc.etc. in other words distribute the affirmations as packets of energy kinda like a computer packet till all the data or in this case energy is done and you perform the final affirmation before directing.
Most people will tell you to perform all the runes and vibrations one after the other for multiple runic expressions. In fact besides finding the right runes to use the harder part is programming. If you use multiple runes rather than one your horizons broaden and you may need to think outside the box. Just like the awakening rituals it's not focused on one form of reality but a broad range of reality.
Not unlike a computer program and having multiple parameters available.