I posted on the same thread HoldAll posted, but I'll add a few more mantras here that also work besides the 22 syllable mantra:
om krīṁ dakṣiṇa kāḻikāyai namaḥ
krīṁ kāḻike namaha
krīṁ hūṁ hrīṁ dakṣiṇe kāḻike krīṁ hūṁ hrīṁ namaha
om krīṁ kalikaye namaha (my personal favorite other than my lineage mantras)
With whatever you choose, I would have some water, a candle, some incense, and maybe also some food. One of those is better than nothing if your circumstances don't allow it. You should also focus on offering your ego, ignorance, desire, and what I call unenlightened-nature.
Each mantra should be recited for at least a full mala (108 times) while focusing either on an image, idol, or a visualization of her. If you want to consecrate a talisman/yantra for her, I would recommend the same book I posted in the other thread. If that is too challenging, DM me and I will help you along
Some advice: She can be very destabilizing at first, and usually operates by cutting things out rather than bringing new things in. You can balance this out with worship of other deities such as Tripura-Sundari, Ganesha, Vishnu, or others.
OM KRIM SVAHA!