Tonya:
First off, please remember that not everyone can look like Cathe! A large part of what makes Cathe look as good as she does is genetics. I, for example, will never look like her. i am not as petite and as compact as Cathe, I am much taller, I do not have the same ability as she has to build upper body muscle, although my lower body is strong.
What you want to aim for is to have Cathe's muscular, lean physique as your goal, but to realize your maximum potential for that within the limits of your own genetic make up. Right? In other words, to be the best YOU that you can be.
I am going to recommend that you invest in a new book by Tosca Reno, called "The Eat-Clean Diet Workout: Quick Routines for Your Best Body Ever (with DVD)". What you need as you start off on this fitness journey is some knowledge. You need a better idea of how to build muscle, how often to train, what exercises to do, how to eat properly, how to create muscle building routines, how to keep track of your success, etc. Tosca got herself into pretty impressive shape, within the limits of her genetic possibilities, at the age of forty. Her book is sensible, full of good guidelines for how to get started and practical know-how.
Then, my next suggestion is that you leave the pyramid workouts for now and buy instead Cathe's Muscle Max DVD. What you need as you start out is a total body weight training workout to learn the sort of exercises you need to do, to help you learn correct form and technique and for you to see how far you can progress lifting increasingly heavier weights, say, three times per week.
Once you feel you have built up a solid foundation of strength and fitness, then go ahead and get the Pyramids. They are slightly more specialized, high intensity testing your endurance. They will then help you reach for the next level of fitness.
Walking is great exercise, but to get that lean look you will have to commit to more than just "walking when you can." Your heart needs more from you than this. Three times a week dedicate yourself to cardio work, pushing the pace, making it a power walk, not just a stroll. Invest in a heart rate monitor and learn about how to pace yourself to burn more calories/body fat to get leaner and more cardiovascularly fit.
Looking like Cathe requires a commitment from you to your total health so yes, you need to clean up your diet and cutting out the sweets and empty carbs is a great start. Many people state that 80% of fitness and being lean is diet related.
Get a few books, get informed, get Cathe's DVD, grab the dumbells and sneakers and get ready to be a healthier, better YOU!
Good luck!
Clare