Well at least to do something unpleasant to it!
In this lovely weather I have french doors to garden open and neighbours cat keeps walking uninvited into our house. This eve after I had closed up for the night I found said cat waiting at the doors to be let OUT about 20 mins later. Where had it been all this time???? Somewhere upstairs I guess.
I have a newborn DS and don't feel comfortable having someone else's cat roaming in and out as it chooses. Plus if I wanted my beds and sofas covered in cat hair, I'd get a cat!
So what do I have to do to teach it it isn't welcome INSIDE our house. The cr*pping in the garden is another thread altogether...