Before giving a bed bath, which action should the aide take FIRST?

While checking the water temperature is important to ensure the client's comfort and safety, it is not the first step. This action should be performed after confirming the client's specific needs in the care plan, as some clients may have particular preferences regarding water temperature.

Positioning the bed at waist height is a crucial step for the aide's ergonomic safety and the comfort of the client during the bath. However, this action should be done after reviewing the care plan to understand the client's mobility needs and any specific accommodations that should be made.

Lowering the side-rail is an important safety measure to facilitate access to the client during the bath. However, this should occur after the aide has consulted the care plan to confirm that it is safe and appropriate for the client, as some clients may require different safety protocols.