I fell while moving a box and my foot / ankle went side ways but the outer side of my ankle has swelling and bruising what should I do?

Hope You Like Rice. The swelling and bruising are both very good indicators that your ankle has been injured. The immediate treatment is using the RICE principles as your guide. Rest your foot. Ice application with some mild Compression. Finally, Elevate your foot. This should minimize the bruising and swelling as well as offering some pain relief. X-ray evaluation may or may not reveal an underlying fracture.
Rule out fracture. There is chance that you have a syndemosal injury which means that they opposite side could have gotten injured. Xray might be warranted here.