1. Go on a weekend. Almost all the parking spots are free of cost. All museums and places of interest are free throughout the year.
2. Make a list of Must Visit Places and set yourself a time limit for visiting each place and stick to it. Most of the places can easily rob you of 4-5 hours of precious time. Know that no one can see all that DC has to offer in a single trip. DC can be very crowded so be ready to improvise on the plans. And no matter how much you plan, you will still be late. Accept it and the tour will be a lot easier.
3. Take one of those Trolley Tours. Do not get down at White House early in the day. Get to the white house only at around 3 or 4 in the evening as this place is quite crowded and getting back into the trolley buses can be a pain.
4. For the months of June and July: Do not take any Trolley Service to Arlington. Arlington Cemetery has very reasonable parking rates. Plan to reach there at 4:30pm to 5:00pm. Walk or take a bus to the ‘Tomb of Unknown Soldier’ Watch the Change of Guard. Proceed to Arlington House. From there, visit and pay homage at the JFK Burial Site. Visit the Women’s memorial. You should comfortably be able to take in all these sights by 7:30pm. Drive to the Marine Corps Memorial.
5. DC has a lot of food trucks and places to eat. It has something for everyone. So unless you have hard and fast rules about what you would eat and what you won’t, DC has a lot to offer on the plate.
6. Save the Lincoln Memorial , Washington Memorial and a stroll around the Basin for the evening when the crowds are thin and weather pleasant.