• Backup your database and files.*  Backup plugin suggestions: BlogVault.net, VaultPress.com, BackupBuddy from ithemes.com. 
• Install and activate Classic Editor plugin (optional, useful if you are not ready to work with the new editor style)
• Update your installed plugins
• Update your install theme
• Update WordPress version to 5.0 (the available version may be different depending on when you are implementing the steps in this article).
• You might see a prompt to allow a database update.

*some webhosting plans include daily backups — ask your webhosting support team if that is an available option for your site