How can you stop your eyes from itching when wearing contacts?

Ensure that your are sticking to your wearing schedule- if you exceed the maimum wear-time of the lenses, they may become irritable.
Make sure that you keep the lenses clean! Dirty lenses are a common cause of irritation. If you don't clean your lenses, you can get a nasty eye infection!
Ensure that you are using the correct cleaning system for your lenses- your optician can advise you.
If your eyes are particularly dry, you could try artificial tears or saline
Are they the correct lenses? Contact lenses come in many shapes and sizes so you should never wear a lens that hasn't been fitted by an Optomertrist or other qualifies person. Wearing the wrong size lenses will make eyes irritable.
Most importantly though, if lenses are causing any pain or discomfort, remove them immediately and book an appointment with your Optometrist.
There is a way other then using color contacts that make your eyes red dry and itchy . You can change your eye color forever with surgery.
The website is newcoloriris.com