What's the best way to find affiliate marketing keywords?

just launched my first affiliate site but struggling to pick search terms that get decent traffic. tried a couple free tools and checking what others rank for but not sure if that’s enough. any better approaches out there?

For affiliate SEO, don’t start with “keywords,” start with buyer-intent SERP patterns: scrape competitors’ top pages in Ahrefs/Semrush + GSC (once you have data), then build clusters around modifiers like “best,” “review,” “vs,” “alternatives,” “coupon/discount,” “pricing,” “for [use case]” and prioritize by KD vs. realistic DR + SERP feature makeup + commercial value (EPC/AOV), not raw volume. My go-to workflow is Ahrefs Batch Analysis + Keyword Explorer + SERP export, validate with Google Autocomplete/People Also Ask, then score each term with a simple sheet: Intent (1–5), SERP weakness (1–5), payout potential, and content type match—you’ll find easier wins in long-tail “best X for Y” and “X vs Y” where top results are thin/dated and you can out-EEAT them.