Minifying removes spaces and comments from code so files are smaller and load faster.

1. WordPress: a caching/optimisation plugin (for example, Autoptimize, W3 Total Cache, or LiteSpeed Cache) can minify and combine CSS/JS automatically — enable those options.
2. Manual: minify files with an online tool and upload the minified versions.
3. Always test your site after minifying — occasionally combining files breaks a script or style.

Tip: If minifying causes a layout or feature to break, exclude that specific file in the plugin's settings rather than turning minification off entirely.