The short answer – as we’re about to see in Australia – is that voters have to be issued with magnifying glasses! As Antony Green explains in this clip, the number of parties on the ballot paper for the next Senate election has become so large that the only way a ballot paper can be printed that remains within the printing limit of one metre (!) in diameter is to use a 6-point font!
At the heart of all of this is the Single Transferable Vote (STV) electoral system, though not as we know it. While we tend to associate STV with Ireland and Irish politics, the fact is that we’re not alone. Malta also uses STV to elect its parliament. And Australia uses it to elect its powerful Senate and also across its various states to elect one or other of the state houses of parliament. Indeed, in many ways STV is an Australian invention: Adelaide was the first place to use this system for a public election for its city council in 1840, and Tasmania has being using STV since 1907.
But the form of STV used for Australian Senate elections in like nothing we’ve ever seen, or hopefully would ever see here (for more details check out your local library for this). The main points of difference from Irish STV are as follows:
- The constituencies are larger and so there are more candidates
- Voters are required to rank order all the candidates that appear on the ballot paper (unlike in Ireland where we can simply rank one candidate if we wish)
- To ‘help’ the voters to complete the ballot papers, the Australians have come up with the wheeze of ‘ticket voting’ where the party labels are arranged across the top of the ballot paper and a voter has the option of simply voting for one party and allowing the party of their choice determine all the remaining candidates on the ballot paper (in effect transforming Australian STV into a variant of a European closed list electoral system). The vast bulk of Australian voters (generally 95% or so) opt to use the ticket vote short cut.
- Because the rules to register a party are pretty lax parties make use of the opportunity presented to them by the ‘ticket vote’ of funneling preferences from more minor parties to them, thus feeding the frenzy of party registration and in turn extending the size of the ballot paper.
The outcome is magnifying glasses for the bewildered voters!
Irish Politics Forum 
The reason voters are “forced” to rank order all the candidates is because the political parties want to control who gets elected rather than leaving it to the voters. The rank all requirement is coupled with the above the line option which makes it “easier” for voters but has the effect of turing it into a closed list system.
STV is too voter friendly for Australian party politicians
I find your bias against the Australian system questionable, considering the failures of the Irish system in a whole range of areas.
The Australian system overcomes most of the disadvantages of the Irish version of PR-STV, and with just a few minor modifications would overcome your big problem with it and 1 or 2 other little issues. In reality it is far superior, fairer and more democratic/proportional than the Irish system.
If I get a chance to post on here as lead articles, I will point out how.