Pretty much just feed her a mouse or rat that is as wide as the widest part of the snake at the widest part of the rat(usually the back hips). If you got a scale, just weigh out a 10-20% sized mouse or rat. I fed my girl every 3-4 days a 10-20% rat until she hit around 433g. Then she went on a once a week feeding of a weaned/small rat. of course she is always hungry still and usually by the fourth day she is out looking for a rat again.