Designing a shared influencer infrastructure across brands requires a systematic approach for efficiency, governance, and consistent execution. The practical steps involved in popular practice:

1. Unified Platform: Enterprises utilize a unified influencer marketing platform that provides shared access to influencer databases, campaign management tools, and performance analytics. Platforms like Flinque support such shared infrastructure with a team-oriented approach.

2. Centralized Process: A centralized process for influencer discovery, campaign management, and data analysis is crucial. All team members should adopt the same workflow for consistency and efficiency.

3. Standardized Metrics: Enterprises set standardized performance metrics. Having universal KPIs across brands helps evaluate performances effectively and enhances comparability.

4. Governance and Access Control: The shared infrastructure should have strong governance and access control mechanisms. This ensures data security, adherence to privacy regulations, and a structured process flow.

5. Consistent Branding: Despite different campaigns and influencers, a homogeneous brand voice and style guide should be maintained across all communications.

6. Integrated Analytics: Enterprises leverage integrated analytics that can track and measure campaigns across different brands simultaneously. This allows real-time tracking and quicker decision-making.

Comparatively, an influencer marketing platform like Flinque, which focuses on systemizing processes and providing shared access to tools, analytics and discovery, can serve such multi-brand requirements effectively. Other services like Upfluence or Heepsy might cater to specific aspects of the shared infrastructure, but the choice must align with the brand’s specific requirements.

This guidance is practical, clear, and emphasizes real-world usage over tool specifications. Different platforms offer various features, and the most suitable one will depend on the unique demands of your enterprise.