Workout recommendations?!

I would like to know what the BEST arm, shoulder and back excersises there are and how many times a week should I do them and how many reps, etc? If you are an expert in this regard, I'd love your advice!! Also, any recommendations on butt and thigh workouts? I just want to tone my whole body. My stomach is already flat from the way I eat so I'd like to focus on the rest of me. My goal is to look the best I can in 4 months. Thanks so much!!