I felt completely prepared for all aspects before and after the surgery. Most all information I needed was on the net. The rest, especially my customized plan, was provided by my surgeon, nutritionist, and bariatric behaviorial therapist.
I read voraciously all that I could regarding the surgery before I even attended my first consultation.
I watched hours of youtube diaries that people have so graciously provided of their surgeries, struggles, successes, and failures. I particularly focused on failures and what people didn't consider before the surgery. I focused on what people ate and what their relationship with food was before and after surgery.
I read every bit of material my surgeon/nutritionist/psychologist provided. The information laid out every aspect of life before and after surgery. Their material covered all phases of eating pre- and post-op, nutrition guideliness, behavioral modification.
I tried out different shakes, Vitamins, and foods to see what I'd like for the pre-op and post-op diets. I didn't really plan menus because I'm a fairly decent cook. I can follow any plan.
I attended (and still attend) support groups to help and discuss the pre- and post-surgery life. Always something new to learn!
I understand not everyone prepares for the surgery for one reason or another, but there's so much that we have to do after the surgery to be successful long-term, that I can't imagine not being armed with all the information I learned.
Best of luck and success to everyone!