I'm with some of the others in that I walk, walk, walk. IN the shoes I am taking with me. I am heading out in Sept for my 6th RS tour and tomorrow is my 8-mile walk day. I will be up to 12 before I leave.
I also have compiled a couple of spreadsheets/checklists so I can check off things. I have a packing spreadsheet with clothes and miscellaneous stuff and I also have a countdown checklist starting a month out up to 24 hours before I leave home. Start taking notes now on what people recommend! Add in to your time frame notifying credit and debit cards, getting Euro ahead if you want some money in your pocket when you land. (This is always a much discussed issue here. Many want Euro in their pockets, others are comfortable going to an ATM when they land in Italy. I'm a have-some-ahead-so-I-don't-have-to-figure-out-a-foreign-ATM when I'm jet-lagged kind of person)
I do trial packing at least a month out. I have a new RS 20" roller I am taking this time and my trial pack was actually a 2-week Road Trip the first of July. I use packing cubes to help keep myself organized altho since if you take V/F/R you only have 3 hotels and 2 moves so staying organized in your suitcase is not as critical as it was on the 21 day Best Of Europe.
Do you all have passports? If not, I think Rick has a deal where he will reimburse you (or credit you) for a new passport purchase when you sign up for one of his tours. Do not wait until the last minute to get your passports. Too much can go wrong. (Nephew and GF headed to Mexico with her Dad last week. She waited until June to get her Passport. Then it was shipped to the wrong address. Not her mistake, someone typed in 9 instead of 4 and it went to a vacant lot. Much anguish. Finally received 2 days before flight. Ugh.)
I usually do some research ahead of time to see what sightseeing possibilities I have in each place, then decide when I'm there what I want to do based also on what the guide suggests. Sometimes on the walks around town with a local guide you see something you hadn't known about. I like the Streetwise laminated city maps so you can see the area where your guided walking tour will be, then see what is in that area.
You will have a terrific time on the RS tour. They guides also teach you travel skills so you can be an independent traveler.