Wow, what a good question to ask and what a difficult one to answer.
Colour – well, medium brown, I guess. If it is too dark then bowel is probably moving too slowly; very black and sticky indicates the possibility of blood in the stools; yellowish and smelling bad, you have an intestinal bug or imbalance of bacteria; very yellow indicates a liver problem; purplish/red, you have been eating beetroot, (note that bright red blood is
usually caused by a bleeding haemorrhoid.)
Shape – evenly formed and holds its shape. If hard and pebbly you are constipated; if it falls apart and is watery you may have an intestinal bacteria or virus, have been taking too much oil, using too many laxatives or anti-acid or too much magnesium (as in Epsom salts/Magnesium Sulphate. (Incidentally, too much sorbitol or mannitol, used as sugar
substitutes can also cause this problem).
In some cases gluten intolerance can alsocause a loose/urgent motion.
If the overall intake of sugar is too high, then the motion can often be bubbly as well as a little loose.
How many motions? Opinion varies on this one. I have heard
the opinion that ideally the bowel should move after every meal, as eating
activates the entire digestive system not just the stomach.
I tend to agree with this, but realise that in our society of fast living and fast foods with rarely sufficient time allowed for eating or digestion, let alone sitting on the loo,
that this is often not the norm and we tend to accept one good, complete
properly formed motion daily as ‘normal’.
Many things can affect this habit the most common being stress (not enough time!) changes in regime (going away on holiday!) medications (tranquillisers, pain relievers etc) or illness.
As for floating bowel motion, commonly known as floaters,
too much fibre can cause this as well as malabsorption of fats.