Before using any facial machine on a client, what should a practitioner ensure?

Ensuring that the client does not have contraindications or skin conditions is crucial before using any facial machine. Contraindications may include various medical or skin conditions that could be aggravated by the use of certain machines, potentially leading to adverse reactions or complications. For example, clients with conditions like rosacea, eczema, or active acne might experience worsening of their symptoms if subjected to certain procedures. By assessing the client's skin condition and overall health, a practitioner can tailor the treatment to be both safe and effective, ensuring an optimal outcome for the client.

The other aspects, while also relevant to the overall treatment process, do not carry the same level of priority as assessing contraindications. For instance, if a machine is fully charged but the client has a condition that contraindicates its use, it could lead to harmful consequences despite the machine's readiness. Similarly, the client’s familiarity with the procedure or their skincare products is less critical compared to ensuring their safety regarding existing health conditions.