What can I do to ease my vertigo when I take a shower I have to hold on to the walls so I don't fall.

Hydration. there are many causes of vertigo but the most common is a drop in blood pressure from dehydration. In addition to drinking more water you might want to cool the shower a little because the vasodilation of your skin drops blood pressure. If these measures don't help consult your doctor to make sure your medication isn't a problem or that you don't have an inner ear or central nervous system issue.