Also, I think for transparency reasons, it would really be nice if the voters understood the system. I'm not too sure I like your attitude toward this is.
I've done some work on "voter education," but I think it will be hard for voters to understand the election until they've already had one under their belts.
The most simplest way I can think of explaning things is this:
In this election, you're going to continue to rank your choices by number, like you always have before. The only difference is that this election will ultimately result in five winners, instead of just one.
To do this, we will divide the total number of votes cast by six to come up with the droop quota—the number of votes a candidate will need to win election. Lower prefences will be used as needed (and candidates who cannot win will be mathematically eliminated) until the vote totals of five of those candidates is equal to the quota.
It has been mentioned before (by myself) that in PR-STV, the person you give first preference to is crucial for the following reason: in each round of voting, your ballot counts towards that person—and no one else—at the highest weight possible (one full vote) until that candidate is either elected or mathematically eliminated from winning.
If the candidate is mathematically
eliminated, your "full vote" moves to your second preference. If your first preference candidate is
elected, then that person's vote total is immediately reduced down to the "droop quota," and the excess votes are then redistributed.
If there are extra votes for the person you gave first preference to, your vote will start working for the person you second preferenced at a reduced rate—the more the person you voted first preference for exceeds the quota by, the stronger your vote will count towards your second preference. (Or, conversely, the more your first preference candidate needed your vote, the weaker the value of your second preference vote gets.)
For example, if there are four voters and two seats to be elected, and the votes are cast like this:
Voter 1: A, B, C, D
Voter 2: A, C, B, D
Voter 3: B, A, D, C
Voter 4: A, C, B, D
We first calculate the droop quota (in Atlasia's case, the total number of voters divided by six; here, the total number of voters (4) divided by the total number of candidates to be elected plus one (3)). The droop quota for this election is 4/3, or 1.33333. A candidate will need at least 1.33333 first preference votes to be elected in the first round.
In this scenario, candidate A got 3 first preference votes, while candidate B got 1. Candidate A is declared elected.
Since candidate A has 1.66667 votes more than needed to win, those extra votes are redistributed based on second preferences. Of those who gave candidate A their second preference, two people voted for C, and one voted for B. Redistributed proportionately, candidate C gains 1.11111 votes and candidate B gains 0.55555 votes.
These are added to the first preference votes still in effect for those two candidates, Candidate B has now exceeded the droop quota with 2.11111 votes and is elected.