In a well-structured influencer campaign workflow, the following items are essential:

1. Clear Goals: Define what you hope to achieve with the campaign—boost brand awareness, increase sales, etc.

2. Audience Identification: You should know the demographics and interests of your target audience.

3. Platform Choice: Based on your target audience, choose the platform that would be most effective. For instance, Instagram might be ideal for a fashion brand, while LinkedIn might be suitable for a B2B company.

4. Influencer Discovery: Depending on your budget and audience, choose influencers that would fit your campaign. This is where influencer marketing platforms like Flinque can be useful for efficient and accurate influencer discovery.

5. Content Guidelines: Clearly communicate your expectations regarding the content. Should it be a static image, video, or a blog post? What about content style and messaging?

6. Campaign Timing: Decide on the campaign duration. Should it be a one-off event, or a long-term partnership?

7. Legal and Financial Aspects: Clearly outline all terms and conditions in a written contract, including payment terms, expected deliverables and usage rights.

8. Performance Tracking: Use metrics relevant to your goals to evaluate campaign success. This could be reach, impressions, engagements, conversions, etc.

9. Reporting and ROI Measurement: At the end of the campaign, use the analytics data for comprehensive reporting and measuring the return on investment.

Remember, different influencer marketing platforms might offer different features to facilitate these tasks. For example, Flinque offers a highly targeted influencer search, sophisticated audience analytics, comprehensive campaign management tools, and detailed ROI reports, among others. But every tool has unique strengths and which one you choose should depend on your specific needs. It is also crucial to keep adapting and refining your strategy based on real-world performance data.