Before the Race
1. Learn the Course Map
Very rarely is a course going to change the day of a race. The race director has set up how they want their swim well before the morning of the race. Typically you're going to get an e-mail with an "athlete's guide". If you don't it can also be found on the race website. In it should be the map to your swim and your distance. Look at it! It seems simple enough, because it is, but it can be a crucial component. If you're doing a sprint distance triathlon and there is also a longer race going on the same day, do you know where your buoys are compared to the longer race? The course maps will help guide the way here. When you know exactly where your buoys should be, this will alleviate some of your race morning nerves. And most good race directors will explain the swim course with everyone gathered at the start the morning of the race. This will almost always confirm what you've already known. In turn giving you a little bump in confidence that you know where you're going.2. Practice in Open Water
Not everyone has access to open water practice, but if you do then take advantage of it. When you've had practice swimming in water where you can't see the black line at the bottom of the pool, you'll begin to notice the little things that are different. Like how much of a straight line you actually swim in when you can't see that convenient black line.
Check around with your local parks and rec departments or ask around at your local bike shops/running shops or tri shops if you have them. If there's an open water swim around, a little research should help you uncover it. If you're lucky like us around Kansas City, we have a small 200-250m open water course available to use that uses small race day buoys at one of our parks. It's great to get practice swimming in and around other people plus moving around those turn buoys. You aren't going to make that kind of move in the pool!
If you aren't fortunate enough to have an open water practice with buoys available all summer: there's two other options to look out for.
On occasion one of the local bike/running stores will hold open water swim clinics designed specifically for your race. Often you'll get an e-mail about this when you've signed up for your race. If you don't then you can send an e-mail to your race director to see if there are any available. Usually these are set up on the actual race course. This is an excellent opportunity for you to practice and get rid of those nerves!
The last option is to find any kind of open swim beach. Usually they'll be filled with kids playing, but you can get to the deeper end of what's roped off (or allowed) then swim there. It's not perfect, but is still good to give you a chance to practice outside of the pool.
Race Morning
3. Cold Water Tip - Double Cap
If your race is going to be wetsuit legal and a cold swim (think 68 degrees Fahrenheit and below) then wearing 2 swim caps can be crucial in saving extra body heat. You can use any swim cap for the bottom, but a silicone swim cap is going to be the thickest and warmest. By wearing two caps, you'll save body heat lost through your head into the water by insulating yourself. Although it won't ward off all the cold on your face, it should make for a more comfortable swim than if you only have one on. 3.5 Wear Goggles Underneath Your Outer Cap With your double cap setup you have the opportunity to put your goggles on over your first swim cap, but under your race-day swim cap. This helps keep the straps secure in position on your head. Also, it keeps them safe from stray hands in the water that could accidentally pull them out position or off your face. Nobody wants to be putting goggles back on their head in the middle of an open water swim, trust me, it's no fun.4. Warm-up
Just like when you go to the pool, a warm-up is going to be crucial to your performance on race day. If you have a coach, then talk to them about how long they want you to warm up for. Most likely this is going to mimic what you do on a normal day at the pool. For beginners it may
mean being in the water 5-10 minutes. As you become more seasoned or if you're a stronger swimmer then it may mean a much longer time spent in the water.
The crucial point here is that your arms get loosened up and ready to go before you run at the water trying to hit your race pace "cold." Cold muscles almost always means slower times and more fatigue.
One other advantage of warming up, if it's a cold morning, is that you can get some water in your wet-suit and start warming up that inside layer of water next to your body. It may seem impractical, but this helps you avoid the "cold shock response" that can happen automatically if the water is too cold.
Essentially if the change in temperature is too great then your body will involuntarily gasp for air and constrict blood pathways. Meaning it's going to be hard to breathe on top of feeling squeezed by your wetsuit and it will take more work to get blood pumping through your body.
Take it from my personal experience, it is not fun. It causes extra stress, fatigue and overall lowers the "fun" factor for the day.