Mark your territory

Remember, what makes you feel more secure(and comfortable) is
having strangers away from you.So go ahead, try this - when you
get on your next crowded subway/bus/train, try to occupy the most
space as possible; keep others AWAY - keep your arms a bit wider
from you, keep your backpack on the back instead of at your feet,
make larger arms gestures whenever possible, etc.You don’t need
to have “clear space” around you to make yourself more
comfortable. Whether you are seated or standing, you can keep the
crowd away from you by marking your territory with clothes,
accessories, luggage, etc. For instance, if you keep your jacket
or luggage in your hand or on your seat, barely trespassing the
space of your neighbors, you are actually making THEM feel
uncomfortable - though they probably won’t be able to see why ;
hopefully they will step back a bit, preys of your evil
space-domination plan.