
Tiger poo is supposed to be the best deterrant :D :D :D
I am not a cat person either and where I lived before I was surrounded by them :D 4 next door alone and our garden bordered 6 other gardens totalling 8 cats between them.
I tried everything that was recommended (apart from the tiger poo :D) and nothing stopped them using my garden as their communal toilet. Cat owners tell you that cats always bury their poo but they don't do they? Middle of the lawn was favourite.
Worst thing we ever did was gravel our tiny front garden which then became a giant kitty litter area :D
I did rig up the garden sprinkler near to the cat 'paths' through our garden and had great delight in sneakily turning it on at appropriate moments but it didn't keep them out, unfortunately.