For the Foundation and for the System, the path is the same: a call, a written offer with the purpose of the work and the deadlines, your acceptance by email or by signing the contract, then the first invoice. The contract comes into being at the moment of written acceptance, not at the first message.
For the Application, the contract is concluded online: you create an account, choose the subscription and confirm payment. The tick accepting these terms is the step without which the account isn't activated.
I reserve the right to refuse an order — if what you ask for doesn't fit what I do, if it isn't the moment for you, or if the subject falls into the list below. A refusal comes with the reason in writing, not with silence.