It's very easy. Since XYplorer is a portable application you don't need to do any uninstalling or installing.
Remarks
The application folder is typically C:\Program Files\XYplorer or C:\Program Files (x86)\XYplorer\, and the application data folder typically %appdata%\XYplorer. The easiest way to go to those folders is by menu Go | Go to Application Folder and Go | Go to Application Data Folder inside XYplorer.
The application data folder is typically defined by an entry in the file Startup.ini located in the application folder. It will probably look like this:
[Appdata] Path=%appdata%\XYplorer