How long the patch stays as new depends on a host of factors - your lifestyle, clothing, and frequency&lenght of the showers you take, for example.
When taking the patch off, there is always the risk of dislocating the sensor as well. Therefore, we recommend trying to keep it on for the whole 14 days. When putting the patch on for the first time, if you leave the paper in the middle section of the patch intact, it might be easier to try and remove it when needed. If you feel you need to change something about the patch but are not absolutely certain you'll be able to remove it without taking the sensor off at the same time, you can put kinaesthetic or sports tape on top.