how do you lot implement keywords in website?

one spreadsheet is the whole system: url, primary keyword, two or three secondary phrases. one primary per page, never the same one on two pages, that's the rule that stops you competing with yourself. then per page: the primary in the title tag, the h1, the url slug, the first hundred words, one subheading, and an image alt where it's honest. secondaries go in subheadings and body. after that, internal links from other pages using that phrase as the anchor. the sheet takes a day to build and then it's maintenance, which is about as maintainable as seo gets.