Taking close-up pictures is an art but hints are always helpful. The three primary problems are: a) depth of field, b) exposure time and c) focusing.
1. To have a decent depth of field, a small aperture opening is necessary (a high f-stop).
2. The small aperture restricts the in-coming light and severely increases the exposure time.  A tripod (or even a monopod, or a tripod used as a monopod) will assist in holding the camera still for the longer exposure time.
3. And a biggie with automatic cameras, the software in the typical camera does not believe that you want to take a close-up. You have to tell it. The icon for taking a close-up is often a flower, like a tulip. When this icon is showing, now the software believes you.
4. But that is only one-half of the story. Often a magnified object doesn't show the sharp edges and high contrast necessary for the auto-focusing software. A trick when using an automatic camera:  place a high contrast item beside the object, focus on it, hold the shutter button halfway down, swing the camera back to the target object and move the camera in and out until it is visually focused and SNAP.