Type the name of the flag set into your quick find to get there. Remember, if you are just trying to complete your list, these lists are in walkthrough-like form, so you had best start with one and just go through each point. If a flag is not there, then you must have it already. And remember you can work backward if you need to; just swap the directions. Good luck.
And all flags are in easy-to-find locations. You will never find one floating in mid-air or something like that, or in the middle on nowhere.