ultrazoom, try positioning the DC about 10-12cm away from the subject (I assume you are using c700uz right?), try full zoom and see if you can get a focus. If not, either move further away gradually, or start zooming out. Have to trial and error and experience it yourself.
Yes at that magnification and focal length it's easy to have camera shake and blurring, it's best to use a tripod. However if you are getting shutter speeds like 1/200s or above, you can try handholding.
actually you can do full zoom when you set to macro mode, but you can't focus at the rated 10cm away, it has to be much further. With the closeup +4 filter, that is alleviated, as in, you can focus at a closer distance with full zoom in macro mode. It is an inverse thing, like the closer you go, the bigger the object will be, but the less zoom you can use in order to focus, and vice versa. So you've got to experiment with different combinations of focus distance and zoom to achieve the largest magnification or the best result you want.