You can tell if your SEO is working by checking if your site appears higher when searching your target words on Google. If your pages start getting more visits from search results and not just from social media or ads, that's a good sign. Free tools like Google Search Console can show which words bring people to your site and how often they click. If visitors stay longer, read more pages, or make more purchases, your SEO is improving. However, SEO takes time, sometimes a few months, so changes might not show right away. Checking your rankings every few weeks helps you see if your efforts are paying off.