Putting on a soft contact lens can be tricky, as it is very delicate and the differences between a lens in the correct position and a lens upside down can be difficult to detect. To avoid the potential pain and discomfort caused by a misplaced lens, take some time to do some tests to make sure you are wearing it the right way.
Steps
Method 1 of 3: Do the "U" Test

Step 1. Place the contact lens on your finger
The rounded side should be down, touching the finger. If it looks like a bowl or cup on your finger, it is in the correct orientation. If it looks like a dome, with the rounded side up, the contact lens is turned the wrong way. If you try to find the shape of a bowl on the lens, you will see it upside down.
If you can't hold the lens evenly, try placing it in the palm of your hand, rather than putting it on your finger

Step 2. Hold the lens at eye level
It is very important that you view the lens from the correct angle. If you view it from different angles, your vision could be confused, especially since you need contact lenses to see well. Look at it directly from the side.

Step 3. Look for the "U"
If the contact lens is oriented the right way, it should have a fairly rounded appearance. It should look like a big letter "U". However, if it is reversed, it will look more like a "V" than a "U".
- Look for a flight on the edges. The bottom of the lens can be tricky, but the edges will spread out to the sides if the lens is upside down.
- If the lens appears wider at the top and the lines do not appear straight, it is probably the other way around.
Method 2 of 3: Do the "taco test"

Step 1. Place the lens between your index finger and thumb
Position your fingers so that they are toward the inside of the contact lens and do not cover or touch the edges. There should be enough room for the edges of the contact lens to move.

Step 2. Gently squeeze the lens
Make sure you don't break it. You are not looking to test the integrity of the lens or the limits to which it will bend. All you want to do is see the shape it forms when you fold it.

Step 3. Study the lens
If the edges point straight up, like a dowel, it is lined up correctly. If it is pinched or rounded outward, like the head of a vase, it is upside down and should be turned over.
If you squeeze it firmly, a correctly oriented contact lens will bend enough so that each edge will bend toward the other
Method 3 of 3: Check the Lens Quickly

Step 1. Find the laser engraving
Some contact lens manufacturers place small laser numbers on the lenses to make this process easier. Place the lens on your index finger, rounded side down. Just look up the numbers by looking at the lens from the side. If they are face up, the position is correct.

Step 2. Check the border color
If you have a tinted lens, it will look a specific way if it's upside down. Hold the lens on your fingertip and lower your hand. From there, look down. If the edge is blue or green, which will depend on the type of tint the lens contains, then it is in the correct position. If the edges look a different color, it means it is upside down.

Step 3. Insert the lens
If none of the other tests seem clear, you may need to insert the contact lens as is. Unless you are wearing contact lenses for the first time, you will feel a definite change by inserting a lens the other way around. You will feel irritation, itching, and discomfort.
However, there can be a bit of confusion, as you may feel similar irritability when inserting a dirty lens the right way
Advice
- When flipping a lens, don't use your fingernails. Soft lenses are fragile and can break.
- Before attempting any process, wash your hands thoroughly. Small dirt particles can become big problems if they get trapped under the lenses.
- Use a cleaning solution to rinse the lens before trying to reattach it.
- By applying a fresh drop of saline solution every minute the lens is outdoors, you will prevent the lens from drying out.
- Use a cleaning solution when caring for your contact lenses. Otherwise, they may be damaged.
Warnings
- Be very careful with the lens. If it falls off, it may no longer be hygienic enough to use.
- Be sure not to let the contact lens dry out when testing, as this can cause it to break.