Now you know WHERE you are going you can start figuring out when you want to go, how much it’s going to cost and what you want to do once you are there.
Travel books and the internet are a great place to start! I usually buy a travel book for the destination. There are lots of options out there and it’s all personal preference. I like the Lonely Planet books. They cover a lot of destinations even those that are not popular tourist destinations. Every travel book has the “hot spots”, “popular points of interest” or “must see” page(s). I find that is a good place to start. It usually gives descriptions of each spot then you can decide if you want to see it or not and how much time you want to dedicate to that spot. The books also usually have an area about typical monthly weather, high and low travel seasons and a blurb about typical cost. All of that goes into play to figure out your WHEN you want to go (and for how long), WHAT you want to do once you are there and HOW much money will you need to do it.
Now that you have figured WHERE, WHEN, WHAT you want to do and HOW much is it going to cost you can start your planning.