Simple explanation
Welcome to Day 15. Week 3 begins. This week you stop being a competent Claude Code user and start being a power user. Today's lesson hands you 37,000 free upgrades in one go. What are Skills? A Skill is a pre-written instruction file that gives Claude Code deep expertise in one specific area. Think of it like hiring a specialist instead of a generalist. Without a Skill — Claude Code knows a little about everything. With a Skill — Claude Code knows everything about one specific thing. A Security Review Skill turns Claude Code into a security expert. A UI Design Skill turns Claude Code into a design reviewer. A Launch Checklist Skill turns Claude Code into a deployment expert. You install the Skill once. It is available in every future session with one short command. Where to find Skills There are over 37,000 free Skills available. Ask Claude Code right now: "Show me what Skills are currently installed and suggest three Skills that would be useful for a non-developer building websites." Claude Code will show you what is available and recommend relevant ones. How Skills are installed Skills are stored as simple text files in a folder called .claude/skills/ inside your project. To install a Skill — ask Claude Code: "Install a UI review Skill that checks my pages for design consistency and accessibility issues." Claude Code creates the Skill file automatically. Once installed, you call it with a slash command: /ui-review Instead of writing a long prompt explaining what to check — one command triggers expert-level analysis.
What to do
The 5 most useful Skills for non-developers: Launch Checklist Skill — checks everything before you publish. Missing pages. Broken links. Missing SEO tags. One command before every launch. UI Review Skill — checks your design for consistency. Fonts matching. Colors consistent. Spacing even. Run this after any big build session. Error Explainer Skill — takes any error message and explains it in plain English with a fix. Better than copying to a new prompt. Content Review Skill — checks all text on your site for spelling, tone consistency, and plain English. Flags anything that sounds too technical. Performance Check Skill — checks if your site is loading slowly and tells you exactly what to fix. Today's practical task 1. Open Claude Code in your project. 2. Ask it to create a Launch Checklist Skill for your project: "Create a Launch Checklist Skill that checks my site before every publish. It should verify: all pages load correctly, no placeholder text remains, all links work, meta titles and descriptions exist on every page, the site looks correct on mobile, and all forms submit properly. Save it as /launch-checklist." 3. Once created — type /launch-checklist. 4. Read through every item it flags. 5. Fix at least one thing it finds. Today's result: You have your first Skill installed and have run your first expert-level automated review. From now on, one command replaces a long checklist you would otherwise have to write from scratch every time.
Copy-paste prompt
Create a Launch Checklist Skill that I can trigger with /launch-checklist. When triggered it should review my entire project and check: all pages load without errors, no placeholder text remains anywhere, all internal links point to real pages, every page has a meta title and meta description, images have alt text, the design looks consistent across all pages, and all forms have working submission handling. Save this as a Skill file at .claude/skills/launch-checklist.md
Course note
Key takeaway
A Skill is a pre-written instruction file stored in .claude/skills/. Install one with a prompt, call it with a slash command. One command replaces a long prompt you would otherwise write every time. Install a Launch Checklist Skill today and run it before every future publish.