If you have a queenly manner, you carry yourself like a queen (or maybe you are one!). Queenly things are fit for a queen, like that tiara you wear on special occasions.
You could also call queenly things (or people) regal or aristocratic. Someone who walks with a queenly bearing holds herself proudly, with excellent posture. And if you go on a queenly vacation, it's pretty luxurious and fancy. The words queenly and queen come from an Old English root, cwen, which means both "female ruler of a state," but also simply "wife."