- put the bowl in a corner. That way, the cat won't be able to push it over.
- switch to a bowl with outward sloping sides, so if she tries jumping on it, she will just slide off it. It may also help if you pick one which has a rubber mat on the underside and a weighted base. This will mean it's much more sturdy, and thus harder for the cat to tip over.
- avoid plastic bowls. These are much more easily tipped over, and they scratch very easily, which can also harbor bacteria which can cause and worsen some health problems, like 'catne' for instance. Try giving the cat a metal bowl, since they're heavier and hard wearing.
- you could also switch to using a drinking fountain. Some cats prefer this since standing water can potentially accumulate smells which they dislike. Moving water won't accumulate the scent.
Hope this helps.