“Bit chilly today, isn’t it.”
OK, remember: answer in agreement as it’s not an actual question; reply straightaway with a comment that includes the words ‘glad’ and ‘coat’, then follow up with a related statement/invitation such as ‘I know! The forecast said it was supposed to be warm all week!’ with a tone conveying mild irritation mixed with surprise but said whilst smiling to indicate this is not actually that much of an inconvenience.
Do not forget appropriate eye contact; be conscious of what your eyebrows are doing; ensure a relaxed posture and perform a surreptitious clothing check to ensure all buttons are in the correct holes, no labels are visible and nothing has been put on back to front or inside out. Bonus points if face completely clean.
At all times, be sure to scrutinise conversational partner for signs (verbal or otherwise) of misunderstanding, confusion, sarcasm, humour, annoyance, boredom or any other mood – actual or potential – whilst maintaining acceptable yet non-specified physical distance and simultaneously anticipating their responses and planning your replies.
I could go on but I’m already exhausted and this encounter was only hypothetical, and I haven’t even touched on the post-encounter analysis, self-reproach and recriminations for not having performed well enough again.
Whilst small talk does serve a number of real, defined purposes, including bonding and defining the social status and relationship between two people, that is exactly how I would view it: as a performance.