How to improve website organic CTR of a ranked website?

There's a number of ways to increase CTR

1. Write better titles
2. Write better Meta Descriptions
3. Use Structured Data (for example, Aggregate Rating to get stars in the SERPs)
4. Have a domain of Good Authority (be recognised)

CTR is very undervalued, and something we should all spend more time on to be honest. 

Matt and  Resh give good advice.

One other thing you can do is to do split testing - A/B testing and see what works. There is a whole science behind this but you can test some basics quite quickly and it is always very interesting to see what works well and what doesn't.

Search engines remain one of the most important traffic sources for websites. By achieving a high rank in the SERPs doesn’t help you if nobody ends up clicking on your content. In that case, your search rank is nothing more but a vanity metric. 

        CTR and search rankings are intimately connected. If you check all the boxes on Google’s relevancy radar but can’t move real people to check out your stuff, the search engine will happily demote you.

           The first stop when trying to improve organic CTR is Google Analytics. Here, go to Acquisition > Search Console > Queries. This screen shows you which search queries bring people to your site. It also displays the queries’ clicks, impressions, click-through rate, and average search position. Further information is available in the Landing Pages menu. Here, you learn similar data about the different pages on your site.

By properly doing on page seo, writing quality content etc. I have applied these strategies on my site ad got excellent result. Here is the link

https://cafesmokers.com/