If the BC (Base Curve: generally only two sizes 8.4 and 8.6) OR the diameter is too large, your lenses will feel uncomfortable. Diameters come in several sizes, although some manufactures have one size only (such as 14.20).
I've found that my personal lenses, Air Optix Aqua by Ciba only came in one size, 8.6/14.20, and were too large for my eye. Conversely, Air Optix Night and Day (formerly Focus Night and Day) come in two BC.. 8.4 and 8.6 but have only one diameter, 13.8. I have a trail pair in currently, Air Optix Aqua with a BC of 8.6 and Diameter of 14.20 and extremely uncomfortable. My Focus Night and Days have a BC of 8.4 and a diameter (no option) of 13.8 and are much better.
Not...wearing contacts
Some people have dry eyes from Accutane - if you are one of them then I would suggest not to wear contacts. If you are have no problems, then contacts should not be a problem.
Yes Alice is wearing contacts because in real life her eyes are brown
No, contacts do not cause acne.
Yes, wearing contacts that aren't yours can severely damage your eyes. Be sure to get contacts that are right for your eyes.
You should not have complications or blindness from wearing contacts. Follow the instructions given by your eye doctor and always keep your contacts clean. Only wear contacts prescribed for you.
Yes, you definitely can get a lifeguard certificate when wearing contacts.
Many types of lubricant eye drops are safe and effective to use, even while wearing contacts. Bausch and Lomb ReNu brand eye drops and Systane Contacts are two lubricant eye drop products that are safe to use while wearing contacts (which will not harm your contacts and will help your eyes).
Only by wearing coloured contacts,
Only by wearing coloured contacts,
no Unless you are getting colored contacts. If not, then you will need a prescription to get contacts. Most eye doctors want you to have both just in case your eyes get "tired' of wearing contacts.
You are given one set of eyes. To be safe, the best thing to do is to set up an appointment with your personal or local optometrist. They can examine your eyes to make sure they are healthy and that you will have no problems inserting/wearing what ever color contact you choose to wear. You need to go back to the optometrist and have your eyes checked after wearing the contacts. Make sure you purchase the correct cleaning material to take care of your contacts and use good hand washing technique when caring for the contacts and your eyes.