Jenn, I wouldn't recommend a Ketonic (no carb) diet right away. Try, a low-carb, high-protein diet.
50/30/20 (protein/carb/fat) %
Get this % from you BMR (basal-metabolic-rate): use this formula to figure out your BMR=weight x 12, equals to calorie consumption that you need daily "to live."
So, for example, if your weight is 100lb...
BMR=100x12= 1200cal a day
(protein/carb/fat %)->600cal from protein/360cal from carbs/ 240 cal from fat
600 divided by 4=150g protein a day
360 divided by 4= 90g carbs a day
240 divided by 9= 27g fat a day
Then, 1200 cal divided by 6 meals=200cal a meal
Now, these are an example for a 100lb person. You change them around for your weight.
Mr.X