only interested person Full backup (files + DB) is mandatory before work. 2) Working environment - Create a staging/clone and work in it (never in production). - Rollback procedure: take a snapshot before critical changes. 3) Initial diagnostics - Check PHP/Apache/Nginx logs and server errors. - Browser console (JS errors) and tests: Lighthouse/PageSpeed/GTmetrix. - Malware scans (Wordfence, Sucuri) and core-file integrity checks. - List of outdated plugins/themes and recent changes. - Database check: table sizes, transients. 4) Fix functional errors - Resolve PHP Notice/Warning/Fatal: find the offending file/plugin and fix the code or replace the plugin. - Restore missing images: check paths, file permissions (644/755), rewrite rules and hotlinking. - Fix broken CSS/JS: isolate conflicts (disable plugins one-by-one), enqueue scripts/styles correctly. - Fix 404s: check permalinks, regenerate `.htaccess`, configure correct 301/302 redirects. - Check responsiveness and fix mobile display issues. 5) Images and media - Convert/serve WebP with fallback for incompatible browsers. - Resize images to actual display dimensions. - Compress images (ShortPixel, Imagify, reSmush.it or equivalent). - Enable lazy-loading (native lazy-loading or plugin). 6) Performance - Caching: server-side (OPcache, Varnish) + WP plugin (WP Rocket, LiteSpeed Cache, W3 Total Cache). - Minify/concatenate CSS/JS (watch for conflicts). - Use defer/async for non-critical scripts. - Implement critical CSS for above-the-fold. - Reduce external requests (fonts, embeds); load fonts locally or use preconnect. - Configure CDN and Cache-Control headers, gzip/brotli. - Database optimization: remove old revisions, transients, unused tables; optimize indexing. - Check TTFB and slow resources. 7) Security and updates - Update core/plugins/theme on staging first, then in production. - Malware scanning and basic hardening. - Configure 2FA, limit login attempts, and whitelist admin IPs if possible. - Check file and folder permissions. 8) Testing and delivery - Test in major browsers on desktop and mobile. - Provide a report: list of fixes, changed files, open/closed tickets. - Performance results before/after. - Describe steps for ongoing maintenance and recommendations to prevent recurrence. - Provide estimated timelines for each task and an overall delivery date. Priorities - First: fix critical issues that prevent the site from functioning (pages/images, fatal errors). - Then: speed optimization and general cleanup.