What is the best way to fit clothes into a small suitcase?

I have a week in Boston/NYC ahead of me and only a carry-on sized luggage. I need to bring stuff like thermals, sweaters, scarves and other bulky things.

What is the most space-efficient way to pack? Should I roll up the clothes, or just fold them over once so they’re thinner? Any other packing tips to make the most of my space?

Thanks!