As a total newbie to the city of Chicago, here are some do's and dont's for visiting the city:
Do check out the Palmer House Hilton Hotel. Even if you don't stay here, it's worth it just to stop in and check it out, especially if you are into historical architecture. We booked our room on hotels.com and got a great deal!
Do purchase a transit pass, they are available at any CVS Pharmacy on the city, we got three-day passes for $14, and it was completely worth it - your feet will thank you!
Don't go out of your way to see "the Bean" in Millennium Park. If it is on your way, by all means, take a look, but if you have to make a special trip them don't bother. There are so many amazing things to see in the city, I was not impressed by this giant mirror.
Do venture into stores that you aren't familiar with, you may find a new favorite place to shop! Our favorite was A'Gaci on State street.
Don't forget your sunscreen and comfy shoes, both are complete necessities!
Do have an idea of what you want to do each day. We thought we would decide what to do once we got to the city, this was a bad idea on our part because we were completely overwhelmed by the sheer number of options.
Do ask if your hotel will hold your luggage before you check in or after you check out. Thankfully ours did, so we were able to continue to enjoy the city even after we had checked out of the hotel room, without having to lug everything around with us.
Hope these tips are helpful (many would apply to other popular destinations!) if I think of anything else I will certainly add to the list!