Silvana,
By looking at your photos, your camera has a macro function. The issues are your depth of field and your flash. To play with the depth of field, try to find out if the camera you are borrowing lets you change the apperature setting. The higher the number on this, the better. The only drawback is that this generally increases the amount of time you need to have the "shutter" open. By disabling the flash, you'll need even more time (look for a lightning symbol on the back). The link tells you to invest in a tripod, which is a must, and shoot outdoors. What it negelects to tell you is that for these long exposures your pressing of the button will jiggle the camera and create an "out-of-focus" look. I recommend that you use the self timer function with your camera-tripod combination. Old school cameras had a shutter release cable so you wouldn't jostle it during long exposures for macro or night shots, but we are way past that these days.