You can use the Same Day Ballot procedure to cast your vote at the caucus if you cannot attend in person.  You can vote absentee for precinct delegates and officers, and also for the presidential preference caucus ( but in the case of the presidential preference caucus, you can only vote absentee if you did NOT sign up to vote on-line).

To use the Same Day Ballot
1) Print off the ballot at within 24 hours of the caucus meeting
2) Fill out the ballot.
3) Put the ballot in a sealed envelope