Makenopromises, no worries! You're not being a PITA...it's much easier to help you prepare than to deal with you freaking out if what you tried didn't work
because you didn't prepare.

KWIM?
One thing means one serving of the same type of food. While it seems like a lot of people started with oatmeal, Dr. A suggests (and I think it's a good idea) that you start with berries, as they have a very low glycemic index. Plus, they're fresh this time of year. You'd have one serving of berries (same kind, technically) each day for a week and see how you feel. Ideally, you'd have them at the same meal/snack each day--like at breakfast every day--so that you could judge whether that time of day worked for you. If it did, you could keep that and then add a starch (like oatmeal or WW bread)--one serving a day only--that you eat every day for a week at the same time.
Granted, this is all the "ideal" plan. Some of us can tell in a couple days if something is causing problems. If so, ditch it and try it at a different time of day, in a different incarnation (i.e. try sprouted bread instead of plain WW), or try something totally new.
Hope that helps!