As I've said in another thread, clinical experience encompasses both patient and medical personnel contact. It is not enough if you are an orderly and don't get to talk to patients or interact with them in any way. It's important to interact with both patients and health care professionals (doctors, nurses, x-ray techs, etc.), because as a medical student, resident, and professional, these are the people who you will deal with on a constant basis. You (and the adcoms) need to know if you like these interactions and can handle these situations. If you volunteer in a hospital, great. Just make sure that you are not just making beds or taking samples to the lab...make sure you are talking to the nurses, the patients, the doctors, in your capacity to do so. Don't overstep boundaries (you're not a doctor yet), but be sure that your experience is meaningful and that you got a real sense of what it is to work in a clinical setting. Like simpleG said, there are many experiences that can count as clinical experiences...explore as many as you can to find your "fit". You can volunteer in a hospital, in a rural or urban clinic, at community health fairs, or you can work in a clinical setting as a CNA, EMT, pharmacy tech, etc.
Good luck.