Review the course, ride it if you can.

Will there be traffic control the day of your event? Not stopping at stop signs is weird.

Are you wearing a wetsuit? If you are, swim in it beforehand. Swimming is different in a wetsuit. Open water if you can, pool if you can't. Just rinse it out really well.

Most swim/bike transitions involve having right off on the bike. Make sure you're in the appropriate gear when you rack your bike on race day.

Veronica