If someone breaches a contract with you and you wish to demand payment for the damages or losses you have suffered as a result, there are several steps you can take:

1. Review the contract: Before taking any action, review the terms of the contract carefully to ensure that the other party has actually breached the contract. Make sure you have a clear understanding of the obligations of each party under the contract, as well as any relevant deadlines, payment schedules, or other requirements.
2. Contact the other party: If you believe that the other party has breached the contract, the first step is to contact them and explain the situation. Be clear and specific about the ways in which they have breached the contract, and provide any supporting documentation or evidence you have.
3. Demand payment: Once you have contacted the other party and explained the situation, you should demand payment for the damages or losses you have suffered as a result of their breach of the contract. Be specific about the amount you are owed and the timeline for payment.
4. Consider legal action: If the other party refuses to pay or disputes your claim, you may need to consider legal action. Depending on the amount of money involved, you may be able to pursue the matter in small claims court or you may need to hire an attorney and pursue a lawsuit in state court.
5. Document everything: Throughout the process of demanding payment and potentially pursuing legal action, it is important to keep careful records of all communications, agreements, and transactions related to the contract. This documentation can be used as evidence if the matter goes to court.

In summary, if someone breaches a contract with you and you wish to demand payment, it is important to review the contract carefully, contact the other party, demand payment, consider legal action if necessary, and document everything carefully.