The email containing the license key contains basic details about activating the product. On the main login screen to the product, there's a prominent link to activate the key.
Since you provide no additional details, I'm not able to offer any further guidance. We usually have someone responding to support queries on Saturdays, so you should get a response. Please be sure to provide support with as much detail as possible so that they can give you the information you need on the first try. Otherwise, if they need to obtain more details from you, it might not be until Monday that you get up and running.