Final answer:
The first step when a patient feels faint is to have them sit down to prevent a fall and injury, then further assess and call for medical assistance if needed.
Step-by-step explanation:
If a patient tells you he feels faint while ambulating in the hallway, the first action you should take is to have the patient sit down or lie down if possible. This helps prevent a potential fall and injury due to fainting. Once the patient is in a safe position, you can further assess the situation and call for a nurse or medical team if necessary. Additionally, asking the patient to take deep breaths can help if the faintness is due to anxiety or hyperventilation, and applying a cold washcloth to the patient's face might provide some relief, but these steps should come after ensuring the patient's safety by having them sit or lie down.