How to add a number to the rep to display how many people +1'ed?

As the title says, here we have a number that displays how many people used the +1 on a post. How can I do this myself?

Bump, since no reply in 26 hours.

It seems to not work with the custom work I've done with the rep system :

Code:

.vote .vote-button, .vote-no-bar {
  display:none;
}
.vote .vote-button:first-child {
    display:block;
}
.vote .vote-button a {
background-image: url('http://cdn1.iconfinder.com/data/icons/basicset/plus_16.png') !important;
background-repeat: no-repeat;
position:relative;
right: 35px;
top: -16px;
padding-right: 25px;
padding-top: 22px;
font-size: 0px !important;
}

Also, note that want pressing the button to add +1 to the reputation field of the user in his profile.

Basically, I want the +1 feature of this forum. That's the most blunt way to put it.