This trick is not the least bit examinable and there is so much heat on the card that you probably
will need a fireman.
You can do a switch, but...seriously...this trick is so powerfully
visual that they wont tear their eyes from it and will notice most attempts to break line of sight.
This trick is AMAZING for social media, but to perform it as walk around you would probably
need to push into the next trick IMMEDIATELY or get caught out. In fact maybe hold a deck in the
other hand with just your forefinger free to do the presentation. That way you can use the deck as a
bit of cover. In fact that is probably the only way I would do it close up or walk around.