One of my favourite sales training exercises is the trading game.
In the trading game you start with something relatively small like a pen or a paperclip and you try to trade it for something of more value, and then you try to trade that for something of more value and then etc. you know what I mean.
Until you got yourself a car :) ( or a real life doll box)
It is not only great way to train yourself in building rapport, making a connection with people and being creative but it is also a great way to train feeling uncomfortable but act anyway.
Face your fears, trade the pen.