Alright. This technique has two methods of usage, but achieve the same result. Fundamentally, Kuebiko is about generating a largely shapeless mass of energy through your chakra that, when it makes contact with another technique, or source of chakra, will establish a spiritual link between yourself and the person to whom that chakra belongs. As per the second note, this can be used on its own, generating a wave of chakra that will simply move through the field in any direction you choose, or alongside another technique. Think of infusion-type techniques, which I'm sure you're familiar with. Do note that infusing another technique with Kuebiko doesn't have any auxiliary effect other than the spiritual link.
Now, for the link itself. Once the link between yourself and your target, which would generally be your opponent, is established, your future Ronin techniques, and all spiritual techniques (e.g. Genjutsu), can be used at half-cost. Half of the chakra will be taken from your opponent's reserves during a technique's creation, letting you save chakra without losing any efficacy in the technique. Another benefit of this is that those techniques will bypass any damage resistance afforded by things like the Yin Specialty. But remember, this only applies to your spiritual techniques.
Hope that clears it up. If so, do you have any other questions?