SEO Strategy for Established Authority Site

Hey all,
Looking for a bit of advice from the BHW community. Currently running an established (old) authority site, which has a huge level of branded/keyword organic traffic landing on the main site index. We've never built out SEO for the site in the past, but have got thousands of legitimate backlinks, social shares, etc.

We've now launched some new functionality on the site (basically new pages) which we would like to try to rank for specific keywords unrelated to the main keyword traffic landing on the main site index. We're incredibly well established, and it looks like our content + domain weight is already carrying us pretty well.

What kind of external SEO strategy would you recommend here? Any recommended suppliers / packages? We want to establish ourselves for the long term in these new keywords.

Cheers,
JFoulds

Since you are looking for long-term results, you should focus on the White Hat SEO. Also, as you already have an authority site, it will be easy to rank them if you point some high authority backlinks to the new pages with a relevant content.

Getting mentions from trusted sites and guest posts from real niche sites will do the trick for you. Make sure you are getting it with high-quality contents.

go for quality guestposting

Guestposting, infographics, audio files, videos.

You want real content when working on websites such as that.

Don't do anything blackhat if the website is already doing really well.

Press Release + Guest Post -> Main site

Buffer site/Video/Blog (I prefer keyworded Youtube) -> Main Site

Web 2.0 + Social Networks + Press release + Guest Post + Edu/Gov -> Buffer site/Video/Blog