Training for my First open water (ocean) mile swim. Any tips?

If it's possible, you'd want to start doing your swim workouts in the water that you will be competing in. Hopefully there is a buoy somewhere in the water to give you a course and to practice sighting. If you go to my web site www.creteswim.com, at the bottom of the page I have links to three free pdf's on open water swimming which can help you.

In the pool, I'd recommend head-up freestyle, swimming entire lengths looking at the opposite wall, making sure to maintain a strong kick to prevent your lower body from sinking. Your eyes can be just above the water, and you can still take breaths to the sides. The saltwater buoyancy of the ocean will make this easier than in the pool. Here is some additional advice noting a key difference between pool and open water swimming:

“Walls vs. No Walls: Turns at the ends of pool lanes allow swimmers to propel themselves with their legs pushing off the wall, giving the arms a momentary rest, and briefly picking up speed with the push. Without the pool wall, the arms are always working until you decide to rest. The net effect is that swimming in open water without walls is slower than in the pool by 10–30%. Therefore, when you look at a map and see a 1-km swim that in the pool might take you 18 minutes, you should calculate 20 minutes or more in open water under ideal conditions.”

Excerpt From
Crete Swim - An insider's guide to sightseeing from the water
Paul Kalas

If it's possible, you'd want to start doing your swim workouts in the water that you will be competing in. Hopefully there is a buoy somewhere in the water to give you a course and to practice sighting. If you go to my web site www.creteswim.com, at the bottom of the page I have links to three free pdf's on open water swimming which can help you.

In the pool, I'd recommend head-up freestyle, swimming entire lengths looking at the opposite wall, making sure to maintain a strong kick to prevent your lower body from sinking. Your eyes can be just above the water, and you can still take breaths to the sides. The saltwater buoyancy of the ocean will make this easier than in the pool. Here is some additional advice noting a key difference between pool and open water swimming:

“Walls vs. No Walls: Turns at the ends of pool lanes allow swimmers to propel themselves with their legs pushing off the wall, giving the arms a momentary rest, and briefly picking up speed with the push. Without the pool wall, the arms are always working until you decide to rest. The net effect is that swimming in open water without walls is slower than in the pool by 10–30%. Therefore, when you look at a map and see a 1-km swim that in the pool might take you 18 minutes, you should calculate 20 minutes or more in open water under ideal conditions.”

Excerpt From
Crete Swim - An insider's guide to sightseeing from the water
Paul Kalas