How to do An SEO Audit : 7 Brutal Mistakes I Found Doing a Real SEO Audit.
Last week, I sat down to figure out how to do an SEO audit properly — not thesurface-level stuff you read in five-minute blog posts, but a real, structured analysis of a livewebsite. What I found surprised me. Not because the issues were exotic or complicated, butbecause most of them had been sitting there, completely invisible, quietly killing the site’sability to rank. This is that story. Why I decided to run a full SEO audit I’ve been building websites for past years ,(check out my website : https://kglimson.com) and like most people in this space, I had a rough idea of what SEO involved. Keywords, backlinks, fast loading times — the usual suspects. But I had never gone deep. Never actually crawled a site systematically, read a robots.txt file with real intent, or dug into Core Web Vitals data beyond a quick glance at a green or red score. The more I read about what a proper SEO audit actually involves, the more I realised that most of what I thought I knew was surface-level at best.The turning point came when a website I’d been working on — one that had decent content, a clean design, and had been live for over a year — was barely showing up in search results. Traffic was flat. Rankings were stuck. And no amount of tweaking the homepage copy or adding new blog posts seemed to move the needle. That’s when I decided to stop guessing and run a proper SEO audit from scratch. Not a two-minute scan with an online checker, but a structured, layer-by-layer investigation into everything that might be holding the site back. So I picked a real website — one that looked perfectly fine on the outside — and spent a full day running it through a systematic SEO audit. I used Google Search Console, Screaming Frog (freetier), PageSpeed Insights, and Ahrefs’ free backlink checker. No paid enterprise stack. Just the tools that most people reading this actually have access to. The goal wasn’t to produce a polished agency report — it was to genuinely understand what was broken, why it mattered, and what to do about it. What surprised me most wasn’t the number of issues I found — it was how long they had been sitting there unnoticed. A well-run SEO audit doesn’t just tell you what’s wrong today. It shows you how long your site has been quietly paying a penalty for problems nobody thought to look for. That realisation alone changed how I think about website maintenance entirely. Here is what I found, broken down across three layers: technical SEO, on-page optimisation, and backlink authority. Part 1: Technical SEO — the invisible foundation The first thing I checked was how Google was actually seeing and crawling the site. This is where most SEO audits reveal their most serious problems, and this one was no exception. The sitemap existed, which was encouraging. But when I pulled it up and cross-referenced it with Search Console, I found seven URLs inside it that either returned 404 errors or pointed to pages that had been 301-redirected months ago. A sitemap is supposed to be a clean map for crawlers—having broken roads inside it is a bit like giving someone directions that end in a dead end. The bigger shock came from the robots.txt file. One line — a single, accidental entry — was blocking an entire product category from being indexed by Google. This page was live, looked fine in a browser, and had been sitting there for over a year. But search engines couldn’t see it at all. That’s a painful discovery, and it’s genuinely common. The speed issues were just as alarming. The site had render-blocking JavaScript loaded in the document head, no lazy loading on images, and hero images that hadn’t been compressed in years. On the desktop, it felt fast enough. On mobile — where most search traffic now comes from — it was a different story entirely. Core Web Vitals, which Google uses as direct ranking signals, were failing across the board on mobile. LCP at 4.2 seconds. Cumulative Layout Shift at 0.18. These aren’t just numbers on a dashboard — they directly influence how Google evaluates user experience on your site, and by extension, where it decides to rank you. Part 2: On-page SEO — where content meets search intent Once I had the technical picture mapped out, I moved into on-page analysis. This is where understanding how to do an SEO audit gets particularly interesting, because the issues are often more nuanced—and more fixable quickly. Title tags were all over the place. Fourteen pages had either missing titles or duplicated ones shared with other pages. Several others had titles that were too generic to compete for anything meaningful. “Home | Brand Name” is not a title tag — it’s a missed opportunity. Every title should tell both the reader and the search engine exactly what the page is about, ideally with the target keyword placed naturally near the front. Meta descriptions were another problem. Twenty-two of them exceeded 160 characters, which means Google truncates them in search results — often cutting off right before the most compelling part. The irony is that meta descriptions don’t directly affect rankings, but they absolutely affect click-through rate. A well-written description is your ad copy in the search results page. The heading structure issue was one I hadn’t expected to find so widely. Good on-page SEO practice means having exactly one H1 per page—a clear, specific signal of what the page covers—followed by H2s that break content into logical sections. What I found instead were pages with three H1 tags, others with no H1 at all, and plenty where the sole H1 read something vague like “Welcome.” These aren’t just formatting problems. They’re signals Google uses to understand your content’s topic and hierarchy. Internal linking was sparse and unstrategic. High-traffic pages weren’t pointing to related lower-ranking pages that could have benefited from the equity. A few deliberate
