Diet is key. You cannot out train bad nutrition.

Make her note EVERYTHING (edible) passing her lips. Even a cup of milo or a glass of milk can throw off calorie intake by several hundred calories which can make a big difference when added up every month. From there, she can make better choices in terms of what she eats and drinks.

Honestly, the exercise at the gym will depend on the body composition she is aiming for - weight loss is going to depend 99.9% on what she eats. Now, if she desires a more toned, stronger looking physique - weight training. If she doesn't mind looking softer and less toned and possibly skinny fat - focus on cardio.

In the long run, attractiveness-wise & health-wise, a balance of weight training & cardio will be best.

And relaaaaaaax~ This should be a lifetime commitment. It is more than a "3 months go all out and reach goal!!!". It is a future of ensuring the only body she has is maintained at its peak. Don't expect everything to be perfect all at once.

Good luck!

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Edited to add:
As for difference between women and men training or eating - there is none. Our gender differences affect how large our muscles get, that is it. Well that and women pop out babies but that has nothing to do with weight training/cardio (except when we have to take leave from training to pop out said babies).

It is different GOALS which you revolve around. You plan the same way regardless of gender. You figure out nutrition & training routine (which is different for individuals), you implement it, you track progress, you keep going. Calculating macro needs is the same for men and women. Micronutrient needs may defer some due to hormones but thats what multi vitamins are for

This post has been edited by shadowz: Jan 26 2013, 10:30 PM