Once you've built your keyword list you are next tasked with matching these keywords to your landing pages. This is important as it ensures we give you the right actions to optimise your website.
But there's a very important thing to note when assigning keywords to pages: we advise you add 1-3 closely related keywords per page, and not more.
This is key for SEO as it's extremely difficult to SEO a page for more keywords, and you'll have a reduced chance of ranking high in Google if you do this.
Why only 1-3 closely related keywords per page? There's a few reasons:
Google LOVES dedicated content around a single topic. Google wants to provide it's users with the most authoritative webpages, and so it's looking for webpages that are knowledgable around a topic. If you are optimising your page for lots of keywords and topics you are diluting the authority that page has for a single topic.
This means also that you shouldn't optimise keywords that Google see's as synonymous on different pages. For example, I should not try and optimise 'SEO for startups' and 'Startup SEO' on different pages. They are the same in Google's eye and so they need to be optimised on the same page. If not, then this is called cannibalisation, and it's bad for SEO!
You can only optimise certain elements of a webpage, and so you are restricted by the length constraints of these elements. 1-3 keywords usually fits nicely.