|Security was totally the Twins idea.|
Everybody that was invited was showing up in ones and twos at one of the bigger rooms at the The Leaky Cauldron. George, or was it Fred, and Lee Jordan met each person at the entrance of the room, shaking hands and thanking them for coming. After a little chatter, they were led to a table full of used and discarded kitchen utensils. They were the Portkeys that would take the guests to the actual location of the main event. Each person was to take one item. Then Fred, or was it George, touched the hand holding the utensil with his wand, it glowed a light blue for a couple of seconds, and then they disappeared.
All but two individuals made it to the event. One was a party crasher who just happened to be in The Leaky Cauldron for a couple of pints. The other was a reporter for the Daily Prophet. How he found his way in was not known at the time. But neither of them were getting out of their temporary holding cell for the next 24 hours.
It was later revealed that the utensils were not really Portkeys at all. It was the invisible sticking powder on Fred, or was it George’s, hand. He shook hands with only two people that day.
Authors can come up with many ways to tell this story. I hope this will give you some ideas to go on.