your attachment is unreadable. what compiler, operating system, and gui library are you using? But it should be a simple thing to place a button wherever you want it and add the text "up" or "down", but maybe a checkbox would be better suited for that.
Just add a button, set it's property to hold a picture, then add the picture of the arrows. In the OnClick event handler change the picture from up to down, or vice versa and set a BOOL flag accordingly. The hardest part is finding the two pictures you want to use, or use the icon editor to create your own.