Using this control knob is easy. First, find the old knob on your stove or cooktop and remove it. Then, select the appropriate insert from the 5 different ones in the kit according to the size of your burner or simmerstat shaft. Insert it into the new white 30mm knob. Make sure the flat side of the D - shaped insert is in the right position. Once the insert is in place, simply fit the new knob onto the shaft. When using the knob, turn it gently to adjust the heat or flame. As for maintenance, clean the knob regularly with a mild soapy solution and a soft cloth. Avoid using abrasive cleaners as they might damage the knob's surface. If you notice any issues with the knob not turning smoothly or if the insert seems loose, check the fitting and make sure it's secure. If problems persist, you can contact our customer service as we've been in the appliance parts business for over 25 years and are here to help.