Must include 3 elements of your choice in the response:
Characterisation and voice
I think you could have a lot of fun with staging the witches and their telling Macbeth of what they foresee for his future. The scene sparks the theme of ambition in Macbeth -- he is presented with the picture of himself as king -- and it is a very tempting picture for a man who has accomplished most everything else he has set out to accomplish up to this point in his life. You could stage it in a traditional way with scary, dark, smokey-misty lighting in a setting that looks like a clearing in a woods. The witches could be walking around their cauldron and singing their chants. The costumes could be typical witch costumes with black pointed hats and long black robes. OR, you could do something more fun. I once saw a production where the witches were signing around a campfire pushing shopping carts full of their "ingredients." They were dressed in modern garb -- like goofy, geeky women who thoroughly enjoyed each others company and had great fun in conveying these types of prophesy to people. There are so many ways to go with a project like this!