Using the Rothenberger Romax Compact III Set M15 - 22 - 28 is quite straightforward. First, make sure you've selected the right pressing jaws according to the size of the fitting you're working with. Place the fitting in the jaws and position the machine properly. Then, start the pressing process. It'll take about 3 seconds to complete a press cycle. When using the Rothenberger App for data collection, ensure your device is connected to the machine. As for maintenance, keep the machine clean after each use. Wipe off any dirt or debris from the pressing jaws and the body of the machine. Check the hydraulic system regularly for any leaks or malfunctions. Store the machine in a dry and cool place to prevent damage. Also, follow the safety instructions provided in the product documents at all times to avoid any accidents.