I did this plan for a previous USA poster who was planning a one day visit. I July the park will close around 10pm or 11pm as it does not get dark until that time. The main night time fireworks show projected onto The Castle will be at park closing. The show is approx 20 minutes. People usually start getting viewing places about an hour before the show. You will need to check park closing time for the day of your visit. For example if park closing is at 10pm, the show starts at 10pm, people start getting viewing places at 9pm.
As you are not staying onsite you will need to check the last train times / bus times. You did not say if you will have a car. The last trains after the park closes can get very crowded.
For just one day, you need to get there about 45 minutes before park opening for general public. Most likely you should get there around 9am and go straight to The Studios Park. Go straight to Crushes Coaster and then go to single rider line in Ratatouille. Take a look in the shop in the Ratatouille area and then exit The Studios Park.
On your way out of The Studios take a look at the shops and get a quick service food. This should take you to 1pm
Go straight to the Main park and walk down Main Street. You wont have time to dawdle or browse the shops. Go direct to Discoveryland and either Fastpass Star Tours or Buzz Lightyear. While you wait for your Fastpass window you will have time to do ONE of the following, Space Mountain or Buzz or Star Tours, depending on which fastpass you decided on.
Once you have done 2 rides in Discoveryland, walk or run to Fantasyland. Exit Discoveryland and head towards the Wishing Well, Pizza Belle Notre, stage side of the Castle. Find the pathway under The Castle to the dragon. Exit the dragon and come up into Fantasyland. Depending on time, check out the upper walk through area of The Castle.
Pick 2 rides in Fantasyland, leaving Peter Pan as your second ride. Exit Peter Pan and walk smartly to Pirates of The Caribbean.
After Pirates get a quick service food in Au Chalet des Marrionettes and then head into Adventure Land.
In Adventureland you have Big Thunder Mountain, Indiana Jones and Phantom Manor.
By this stage it should be evening time and you should get some more food. Depending on time you could do a table service. Depending on park closing time you will probally have time to do 1 more ride or do some shopping before heading back to Main Street to find a spot to watch the night time fireworks and animation show projected onto The Castle
Skip table service meals, skip parades, skip character meet and greets, skip wandering about the shops, skip shows and you should be able to fit in my touring plan