For any given substance, the heat capacity of a body is directly proportional to the amount of substance it contains (measured in terms of mass or moles or volume). Doubling the amount of substance in a body doubles its heat capacity, etc.
Conventional soft contacts can last up to a year; conventional rigid gas permeable (RGP) contact lenses can last even longer. Frequent or planned replacement contact lenses last one to several months. Disposable contacts last from one day (daily wear) to up to two weeks (extended wear).
Then, you may wear four hours on the second day. By parity of reasoning, you just add two hours every day to wear contact lenses until the fifth day. However, after you have adapted to wearing it, you should keep in mind that not wearing contact lenses more than 8 hours every day.