To use multi-sourcing and hybrid-sourcing models effectively, you need to adopt some best practices. Firstly, you should define your IT outsourcing objectives and requirements clearly. This means identifying your business needs, priorities, and expectations for each IT function or project, and communicating them to the potential vendors. Additionally, you should create criteria and metrics for evaluating and selecting vendors. Secondly, it's important to choose your IT outsourcing partners carefully. You must conduct a thorough due diligence and assessment of the vendors' capabilities, track records, and reputations. You should also negotiate and finalize the contracts, terms, and conditions with the vendors to ensure fairness, transparency, and flexibility. Lastly, you must implement a robust IT outsourcing governance framework. This includes assigning roles and responsibilities for managing and overseeing the multiple vendors, establishing processes and procedures for communication, coordination, and collaboration. You should also monitor and measure the performance of the vendors and provide feedback, recognition, and improvement.