The best way to explain SEO on your resume is to highlight any task that you have done to increase a websites’ traffic. So if you have rewritten content to make it easier to read, put it on your resume. If you have added internal or external links to a website. Put that on your resume. So anything that highlights the impact you have made. Here are a few more examples you can include: Rewrote Title tags and Meta descriptions to make them keyword rich, Added meaningful Alt text, Performed Blog outreach to increase Backlinks, Add Schema markup to increase click through rate, Used SEO tools to perform Keyword research. Again, just think back to previous positions you've worked and mention any skills that are relevant to a recruiter.