Off-page, you certainly have your work cut out for you. LinkedIn, Facebook, and Twitter have trust and longevity in search engines, as well as domain authority. It will be difficult to outrank them, not just at first but ever, unless the individual does not have a profile on LinkedIn or you have a long tail query that your users may be targeting and that query will be somehow reflected on the page.
That said, think long and hard about your information architecture. How many paths are there to each profile? What are the main sections following your home page? Consider the categories (which should probably be indexed in search) versus tags (which should not be).
From the start, get your canonicalization right. Choose a canonical version/scheme for all your profile pages and make sure that all other URL's (which might include tags, filters, etc.) point to it. You want one strong page for each profile in the index, not several weak ones. Your non-canonical pages should still be crawlable, but only one canonical page should appear for a profile, article, etc. Plus, make sure those URL's are readable (example.com/developer/bob is better than example.com/er568924/nbt98irp). Pay attention to how you want your title tags to appear on your canonical indexed pages too, and standardize that.
Think about internal linking and ensure there are no unintended orphaned pages. Go through your pages and make sure you are not indexing thin content.
Make sure you are not noindexing important pages, and that your robots.txt file isn't accidentally blocking an important section.
Take a look at Google's structured data schema search gallery and choose the schema to implement on your canonical pages, such as articles and job postings. When in doubt, examine LinkedIn's pages and see how things are implemented there.