As they say, you only have one time to make a first impression.
I disagree. I have back peddled before and changed that first impression to an impression worth remembering. You just have to make that second impression is grandiose enough that they forget the first. Yes, it may require a broken limb or worse, but you have to make your impression on future friends or clients as positively memorable as humanly possible. It may require a steak dinner or maybe even a free trip to Vegas, but it has to be great!
Leave your new contact with an impression that it was to his/her benefit to have met you. Make them walk away with a smile. In return you will have gained a life long friend or client.