For the first tier, you want to focus on high-quality, authoritative links. These could come from guest posts, niche-relevant blog posts, high Domain Authority (DA) sites, and editorial backlinks. Ensure these links are from trustworthy sources because they directly link to your website and influence your rankings.
For the second tier, you can use a broader range of links, such as blog comments, forum profiles, web 2.0 properties, and social bookmarks. These links help strengthen the first tier, improving the effectiveness of the entire link-building process. However, be careful with automation and quantity over quality—make sure the second-tier links still come from reputable sites.
Make sure the process appears natural to search engines. Diversify your anchor texts and avoid over-optimization.
This method, when done right, can help improve your site's visibility and rankings, but it requires careful planning.