Flow cell maintenance has been described in the user manuals. In addition, this tutorial contains movies that show the procedure in more detail. Before using this material read the instructions and warnings in the user manual.
Same for both:
ROXY installation with µ-PrepCell in 2 minutes: click to download or watch the movie (right click and "Save link as..." if movie player does not start in your browser). If your player does not recognize the format, download the free player from VLC (Windows or Mac).