In what way does The Old Man and the Sea appeal to our senses, especially colours, taste and touch?

Your question seems to be referring to the way in which
Hemingway uses imagery in this excellent allegorical novel. Imagery is a term given to
the way in which an author paints an image of what he is describing by appealing to as
many of the five senses as possible: sight, taste, touch, smell and hearing. The more
senses that are appealed to, the stronger a sense of the picture that the author is
trying to paint.

There are a number of excellent examples
of imagery in this deeply descriptive novel. Notice the following example of when
Santiago guts a dolphin that he catches on his epic
voyage:

He
felt the maw heavy and slippery in his hands and he slit it open. There were two flying
fish inside. They were fresh and hard and he laid them side by side and dropped the guts
and gills over the stern. They sank, leaving a trail of phospherescence in the water.
The dolphin was cold and leprous grey-white now in the
starlight...

Notice how, in
this quote, Hemingway combines the senses of touch and sight. He describes the feeling
of the maw of the dolphin and the hardness of the two flying fish, and then the coldness
of the dolphin's corpse, just as he describes how the corpse looks "leprous grey-white"
in the light of the stars. Likewise, when he drops over the guts, we see the trail of
phospherescence in the water. This is a good image because it combines two senses to
helps us see the scene that Hemingway is painting. Hopefully this example will help you
to find other examples in the book. Good luck!