We should begin with some safety warnings about wormwood , it is considered toxic and is not meant to be consumed or inhaled due to the toxicity of the herb, so please use with care because we care.
Now, wormwood is by far one of my most valued herbs i use consistently in the arts and one i hardly ever go without. When i began working with spirits and learning about astral projection, wormwood was mentioned to me as a way to contact spirits and open my sight. You can burn this herb (in a ventilated area), it can be used to anoint, and also drank if you know the know how. Which if you go to Witchipedia as a general source and look up wormwood it actually shows you other ways it can be used and your link for that is below.
When preparing for a big ritual or spell despite the use of energy and infusing different energies, i sometimes require the help from my past ancestors. First i clean my house physically and make sure everything is where it needs to be, i do this for two effects, if you ever heard the term "As above so below" you understand the first, and second because i just work better in a clean environment. The second i do is set out an offering for my ancestors, i may even cook a favorite meal of theirs, or leave earthly pleasures they enjoyed while living. Sage is then burned all over the house to finish creating a negative free atmosphere. Fourth everything i need for my spell is laid our before me in perfect access. Last i mix various herbs with the wormwood that normally have something to do with positive energy and/or spiritual communication and burn them using a charcoal disc.
Once you get to that point its your next steps are all personal preferences, normally i would use my voice to call my spirits and it various with what im doing on what is said. Wormwood is defiantly a powerful and useful herb for my favorite C's and that's to communicate, curse, and conjure. Again please be careful if you choose to use this herb, as its effects are both powerful and harmful. Good luck on your witchcraft and happy holidays!