Legal Project Management - To draft a Will in UK

Benny had signed a three-page paper entitled "My Last Will & Testament" last week during his birthday party celebration at a local Club. Benny signed the Will while he and his two friends, Roger and Betty, were having wine together. Benny is concerned with the Will he has prepared. He claims that the Will was made under the influence of alcohol and has approached you to a draft Will for him. Benny shares the following: Benny has intention to leave his house at Orchard to his daughter, Catherine. He wants his grandchildren to be given gift $25,000 each but his grandchildren must only receive the money if they graduate from college before turning 25 years old. His shares to be equally distributed amongst his siblings. He intends to give Charitable Trust of $500,000 for the underprivileged children in Indonesia. He appoints Kiran, Ryan and Sheila as his Trustees for the Charitable Trust. The trustees are given the power to decide the beneficiaries of the trust. His son, Sam to benefit from the residuary estate. This gift is only valid if Sam graduates from a law school. He appoints his cousin, Jessie and Molly to be his executors. Sarah and Melvin are appointed as the guardian and Trustee for his stepchildren, Renee and Raina. He has intention to leave $150,000 each. The money is to be taken from his Australian bank account. He leaves all his paintings to his Aunt Beatrice but he is concerned that she would predecease him. He shares that his niece, Clara Wong is the alternative beneficiary if Aunt Beatrice predeceases him.

Benny has asked to draft Will based on the above information. Please provide more clauses to draft a Will which protect the beneficiaries.