By now, you've likely seen all the "gurus" in your Facebook feed. Some of them are more popular than others. What you'll notice is that the ads you see that have the highest views and engagement are normally the most successful. Use a site like Similar Web to study those ads and see what they're doing. Join their lists and embed yourself in their funnels. That's an important part of the process so that you can replicate and reverse engineer what the most successful marketers are doing.
Concerning broken link building, it can also sometimes be relevant to scan the whole domain (e.g. if the website is a blog within a specific niche as these often feature multiple articles closely related to the same) for broken external links using e.g. XENU, A1 Website Analyzer or similar. (Just be sure to enable checking of external links before crawling the website.)