I always make sure I have plenty of liquids and pain meds and motion sickness meds if I have to do car rides longer than and hour and a half.

A seatbelt cover always makes me feel a little better with my sensory issues. Compression socks and gloves may help with swelling! Breathable clothing, layers, maybe something to keep your hands moving- I don’t know if you do any crafts!

If you do end up needing to do something to keep your hands moving, I recommend something that doesn't require you to look down at your hands. Talking from experience there, it makes me motion sick to do that, but there's plenty of activities and figits that don't require looking.