Create a simple contract by making an agreement with a second party and then exchanging something of value based on that agreement. The contract does not always have to be in writing as long as those two provisions are met, though some states do require written contracts for certain specific transactions. An example of a state-mandated written contract is when there is real estate involved.
Enforcing a simple contract depends largely on how the contract is presented and accepted. An oral contract, for example, is more difficult to enforce than a written one. In addition to states requiring written contracts for certain transactions, they also may require a written contract if the agreement is to last for longer than a minimum time.
Written contracts usually include the signatures of the parties involved. This helps during contract enforcement to prove that both parties agree to all of the major provisions of the contract. A witness signing the agreement also helps in enforcement.
Witnesses are required to be present when a contract is contested, however, so many contracted parties sign in front of a notary public. The notary signs as well as stamps the contract with a seal, showing that the parties involved signed the document. When a notary is used, it is assumed that the signing is valid, and the notary need not take part in any contested dispute.