Either a long top with leggings or dress with tights. Do not wear skinny jeans on a long haul flight. 
As to planes being cold - they're always too cold for me. I don't like using the blankets as they get all static and cling to you.. But I have no choice when it's cold

As to planes being cold - they're always too cold for me. I don't like using the blankets as they get all static and cling to you.. But I have no choice when it's cold
