ve read in some EAs book (baneful magick, if I recall) about this, would anybody who uses this, care about explaining how are they implemented, please?
I craft them via energy work. Drop mind, gather energy, mold it, and give it an intention. You can make them keep out a specific type of energy, or even repeal a specific type of energy. You can even anchor them to a physical object.
Using the chaos sigil method, runes, or a statute. Load it with energy and intention, and feed it periodically.
I hope that answers your question.