As someone who's managed high-volume inboxes for years, my first step is creating multiple email addresses. Categorize them for personal contacts, work, ads, or newsletters. For spam defense, use temporary services like Mail-temporaire.fr or Jetable.org—they create short-lived addresses (minutes to weeks) that forward to your main inbox before vanishing.
Next, let automation handle the heavy lifting. On Gmail, click “Other actions”; on Yahoo, “Action”—then set filters to route emails to folders by sender, keywords, or size. Outlook users go to “Tools” > “Rules and Alerts” (a bit more involved, but powerful). This ensures that crucial message doesn't get lost amid 2,000 emails from Cécile de Rostand at Venteprivee.com or Sophie from Brandalley.
Complement automation with manual organization: create folders like Photos, Invoices, or Invitations. A quick drag-and-drop makes retrieving emails lightning-fast.
Finally, declutter regularly—delete outdated or irrelevant messages. No filter is foolproof, so always scan folders (including spam) before emptying, just in case your boss's email sneaks in there.