It is recommended that colored contacts should be soaked for a good time of 6 - 8 hours before the very first use. The best practice is to soak them in multi-purpose solution for a night. This is done because the solution in which colored contacts come is for storing them. That solution is definitely not meant to come in contact with eyes. If colored contacts are worn without soaking them; you will probably develop pink-eyes or stinging/burning feeling. Let them get neutralized before inserting them into your eyes.