These are just some fun idea that can be added to giants.
Add lights, even just a string of fairy lights draped round your giant can look good. If its a scary giant, eyes that light up can be interesting.
Add a voice. If you have someone technical, a small portable speaker can be fixed inside with a remote microphone can make your giant talk to passers by.
Add a video camera. Low cost video cameras can be mounted on your giant to give a giants-eye view of what is going on around them from 3 meters high!
Your giant can be anything you want to make it, there's even a headless giant!