This video describes the use of lyte prep (Golytely or Colyte or PegLyte or Klean-Prep) that comes in 4 litre containers.
If your doctor prescribed Pico-Salax, click here for more instructions.
Inside a box of Pico-Salax, there are two sachets of Pico-Salax. Dissolve one sachet of Pico-Salax in 150 ml (a mug) of cold water (and drink it) when the video directs you to start drinking your liquid laxative. Following drinking Pico-Salax, drink 1.5 to 2 litres of a variety of clear fluids or sports drinks (do not drink water alone).
When the video directs you to start the second half of your liquid laxative, dissolve the second sachet of Pico-Salax in a mug of cold water, and drink it as before. Then drink another 1.5 to 2 litres of a variety of clear fluids or sports drinks.