Incompatibility of evolution and Christianity

In talking with my full-blown Christian sister, we have come to an impasse. I keep trying to convince her of the scientific evidence surrounding my belief against any deity, most notably evolution. This does nothing to sway her and she always retorts, "well God is all powerful and could have started evolution if he wanted to and the constant change is all part of his plan." I am still not as grounded in my science and philosophy as I someday hope to be. For this reason can you help me pinpoint some ways I can respond. Thank you.