A character is standing alone at a bus stop on a dark road in a dangerous neighbourhood, how might you convey their fear and tension the character experiences through your physicality?

I would use a combination of posture, expression and movement. To convey the character's uncertainty about the potential dangers, sudden swivels of the head may be used to suggest the acknowledgment of an unknown sound, this would convey the character's nervous state through the rapidity of their head motion – suggestive of a desperate need to know the source of the sound and therefore insecurity. Additionally, I would build the volume and pace of the character's breathing in order to convey their growing fear of the unknown, this may be paired with an increasingly rapid rate of eye movement from side-to-side, implying the character is scanning their surroundings faster and faster as they become increasingly nervous. Furthermore, if the character is stood, they might start with their hands in their pockets, indicating a more relaxed mind-set, but as they become nervous their hands can be removed and curled up into tight fists, their arms rigid by their sides, to convey either a gradual paralysis with fear or an attempt to draw themselves into a combative stance, in preparation for any possible confrontation. Finally, movement might be incorporated such that the character gradually begins to back away from the edge of the road (into a wall say) so that they nothing can surprise them from behind, again reinforcing their paranoia.