So once you have decided where you want to go and decided that you want to plan it all yourself, the fun really begins.
I find, during the initial planning phase. A spreadsheet is a good tool to start with.
The first column in my spreadsheet is a date column, and the date is formatted in full to include the day of the week. For example
Sunday 1 Feb 2020. I copy the date down, so that I have one row for every day I plan to be away.
Once I have the dates laid out. I type the country/city that I plan on being in. Try to make sure that your destinations are in an order that means you are taking the most direct route, and not crisscrossing backwards and forward. Google maps is very helpful in this regard.
Once I have a rough plan of where I want to go, I Google the top 10 things to do in each place. This helps me to make sure that I am allowing enough time in each place to go and see the things that excite me the most. Remember that you can’t fit everything in.
I would suggest that you don’t over plan. I really like to be organised, but I also like to leave some time to wander around each place, and to get lost in the culture of where I am. I would however plan in advance any day trips or tours to very popular monuments or museums. If there is something you would be really disappointed to miss, book it in advance and if you can afford to pay extra to “skip the line” it is certainly worth it, if you don’t have time to waste. For example if you would be really disappointed to miss going to the top of the Eiffel Tower book a skip the line tour. Its really great to have a guide, and bypassing the huge queue was really great.
The other thing to think about when planning your itinerary, is to consider what it is that you really love doing. If you don’t spend a lot of time at home wandering through museums and art galleries, I would be very surprised if you would want to spend a lot of time on your holidays doing those things either. There is of course some exceptions, you can’t go to Paris and not see the Louvre.
Once you have your days loosely planned out you will be able to identify if there is anything you want to do that you will miss out on because of the day of the week . For example if you were looking to attend a market in London that only occurs on a Saturday, and you won’t be in London on a Saturday. Those kinds of things will become obvious, and may lead you to change the order of your itinerary.
Don’t forget to allow for travel time, there is no point scheduling an activity for 3 pm in a place that you don’t arrive in until 4:30 pm. I always try to leave our day of arrival in a new city or town free of any activity that involves being somewhere at a specific point in time. I learnt that lesson after booking a tour of Alcatraz in San Francisco for 6:00 pm only to have my flights delayed several times and I didn’t arrive at 6:30 pm.
Your itinerary will evolve over time but the important things to get right early, is your date and time of departure from home and your date of return.