When you sign up for an account, you are asked to provide your credit card information. This information is used only to verify your identity and let us know you’re not a robot. Your credit card is not charged during the verification.
Once your credit card is verified and a desktop is assigned to your account, you can start gaming.
Every 2 weeks, a billing cycle ends & the consumed hours will be billed.
More information about the billing can be found here.