How to Open Your Eyes Underwater Without Goggles on and Not Hurt
Opening your eyes underwater without goggles on can hurt, but there are a few things you can do to reduce the pain. To practice opening your eyes underwater, first, try squinting to help your eyes adjust. If it's not too uncomfortable, slowly open your eyes wider. Close your eyes for a few seconds if they start to sting and then try again when you feel ready. As you get used to the feeling, practice opening your eyes wider and for longer periods of time If your eyes sting after swimming, apply a few drops of a saline solution to soothe them.
Avoid chlorinated water. While you may not always be able to choose where you're going to swim, it is helpful to know which kinds of water cause the most eye pain. For example, chlorinated water (like you will usually find in pools, hot tubs, and so on) tends to hurt more than ordinary water when it gets in your eyes. While it's great for killing waterborne germs, the redness and stinging you can get after a dip in the pool can be seriously annoying. Chlorine hurts more because it disrupts the eye's natural tear membrane. In some cases, chlorine can also dehydrate the cornea, leading to cloudy, distorted vision for a short time. Avoid salt water. Another common source of eye irritation while swimming is salt water. Salt naturally draws moisture out of the eyes, dehydrating them and causing a stinging sensation. In addition, the sorts of places where you're likely to swim in salt water (like beaches) can have additional contaminants in the water like biological matter, silt, and pollution. The eyes are naturally covered with a salty fluid (you are probably aware of this if you've ever tasted your own tears). However, the average salt content of the ocean is usually about three to four times more salty, leading to the imbalance that dehydrates your eyes. Remove contact lenses before swimming. Most optometrists (eye doctors) recommend against swimming with your contacts in. Depending on which type of contacts you are wearing, the water can cause the contact to deform and press against the eye, causing pain. Contacts can also trap bacteria and microorganisms from the water against the eye, which (in rare cases) can lead to infections that cause serious vision problems. If you must wear contacts underwater, use single-use disposable contacts and discard them after you swim. This way, you won't need to carefully disinfect them. Have a soothing saline solution handy. Saline solutions contain a mix of salt and water that is specially formulated to match your eyes' natural salt levels. Applying a few drops after swimming without goggles is a great way to flush contaminants out of your eyes, soothe stinging, and reduce the risk of infection. You can usually find bottles of saline solution at pharmacies and grocery stores for fairly cheap. In a pinch, you can also splash your eyes with cool, clean fresh water like you'd get from a bottle or the tap. Squint, rather than opening your eyes completely. The less you expose your eyes to water, the less you'll irritate them. If opening your eyes all the way is too painful, you may be able to get some underwater vision by simply squinting. You won't be able to see as much, but you will still probably be able to make out vague shapes and outlines, which is better than nothing. Enter the water with your eyes closed. Like any difficult skill, the best way to learn how to open your eyes underwater without pain is through practice. Start by jumping into your preferred body of water. As noted above, clean fresh water is best — chlorine and salt water hurt more. Keep your eyes closed as you enter the water to prevent water from splashing into them. If you're wearing contacts, don't forget to take them off before you get in the water. Try squinting at first. Once you're underwater, open your eyes ever-so-slightly. Crack your eyelids open just a little bit until you can see the vague outlines of your surroundings. Maintain this for a second or two. If it's not too uncomfortable, proceed to the next step. If squinting is too painful, you may be swimming in eye-irritating water (or may just naturally have sensitive eyes). Try the "controlled environment" step at the end of this section. Slowly open your eyes wider. Now, gradually open your eyelids to their natural "open" position. It may be hard to get yourself to do this — it often feels "wrong," like swallowing a pill without water or looking over a high ledge if you're afraid of heights. If you're nervous, go extra-slow to keep your anxiety manageable. Some people find it easier to open their eyes underwater if they look upward. Try experimenting with pointing your eyes in different directions to find a position that feels best for you. Close your eyes as soon as they start to sting. If you've ever held your eyes open out of water (like for a staring contest), you probably know that they start to sting after a while even without anything irritating them besides the air. When you're underwater, your eyes will start to sting much more quickly and you'll need to hold them closed for longer than normal to get the stinging to go away. As soon as you feel the first twinges of pain, shut your eyes and hold them closed for a second or two. Your eyelids will re-coat your eyes with a protective layer of tears, reducing the pain. When the stinging goes away, gradually open your eyes again. Repeat this pattern as you swim underwater to keep the pain under control. If you're having trouble, test your skills in a controlled environment. Everyone's eyes are different. Some people will find it easy to open their eyes underwater, while others may struggle. If you can't seem to get your eyes open, try this gentle practice method until you're more comfortable: Fill a bowl or sink with clean, clear, warm (not hot) water from the tap. Lower your face into the water with your eyes closed. It should feel nice. If it's too hot or cold, adjust the temperature. With your face in the water, gradually open your eyes, squinting at first and then opening them fully. Close your eyes again as soon as they start to sting. Repeat a few times until you can open your eyes confidently before testing your skills in the pool, at the beach, etc. 
Avoid chlorinated water. Avoid salt water. Remove contact lenses before swimming. Have a soothing saline solution handy. Squint, rather than opening your eyes completely. Enter the water with your eyes closed. Try squinting at first. Slowly open your eyes wider. Close your eyes as soon as they start to sting. If you're having trouble, test your skills in a controlled environment. 