The formation of the contract is where the contractual journey begins; if no contract is formed, neither of the parties can be under any obligations. Therefore, it is very important to have an understanding of each part of a contract's formation.
In order for a legally binding agreement to be formed, there are four basic requirements to be met:
2.1 Offer
2.2 Acceptance
2.3 Certainty & Intention to Create Legal Relations
2.4 Consideration & Promissory Estoppel
Reference:
- CIPS study guide page 28-42
- Formation of the contract
LO 1, AC 1.2

Advantages and Disadvantages of using model form contracts.
Model form contracts save a lot of time and money. They are written by industry experts and the buyers and suppliers both understand what is included in the contract.
They are mainly used in Construction and term maintenance contacts. Typical ones are JCT and NEC.
Without the use of model form contracts the buyer and supplier will take a long time to write the terms, negotiate and finalise the contract.
This is time and money wasted.
However, model form contracts require buyers and suppliers to have training so you understand them.
Finally, if you are a buyer in a powerful position you cannot exploit that with a model form contract as these are written for mutual benefit.

Reference:
- Procurement Study Buddy on Facebook
- CIPS study guide page 147

There are a number of ways for an offer to be terminated. They are events that may occur after an offer has been made which bring it to an end so that it can no longer be accepted. An offer is terminated in the following circumstances:
1. Revocation
2. Rejection
3. Lapse of time
4. Conditional Offer (or Failure of Conditionality)
5. Operation of law
6. Death
7. Acceptance
8. Illegality
Reference:
- How Is an Offer Terminated?
- CIPS study guide page 31-32
LO 1, AC 1.2

Consideration is one thing given in exchange for another.
In this case, considerations of customers are three wrappers and 1s6d. Consideration of Nestle is Rockin' Shoes record or a voucher.
Reference:
LO 1, AC 1.2

When a written contract is based on oral negotiation, to avoid the conflicts between orally negotiated terms and final written contract, the contract should include an express term that specifically excludes all prior oral discussion. However, orally negotiated terms can be used to interpret the final contract.
This practice (excluding prior discussion) is so common in international commercial contract that UNIDROIT Principles of International Commercial Contracts have an article (2.1.17) dealing with this.
Reference:
LO 3, AC 3.1