You need what is called an 'allen wrench'. It's a tiny 6 sided shape. I'm not sure of what size a Fender bridge takes but it shouldn't be hard to find. When you do get the correct allen wrench, you're going to want to adjust very slowly. To raise a saddle, you'll have to turn it right (clockwise). You should raise each side of the saddle evenly for the most part. Again, do it very slowly. If you had this guitar set up by a tech, they probably have it adjusted to the best position, so if you want it raised I wouldn't raise it too too much at all.