1. Know which backup you actually need. "Backing up QuickBooks Online" usually means one of two things: a quick export of your current lists and reports to keep somewhere outside QuickBooks, or a genuine restorable snapshot of the whole company. The built-in tools only really cover the first one well.
2. For a snapshot export, click the gear icon and select Export Data. On the Reports tab, set the date range you want covered. Toggle which reports and lists to include using the sliders on the Reports and Lists tabs.
3. Export to Excel. Click Export to Excel, and QuickBooks packages everything you selected into a downloaded, zipped file of spreadsheets. This gives you a readable copy of your data outside QBO, but it isn't something you can later re-import to restore the company exactly as it was.
4. If you're on QuickBooks Online Advanced, use the built-in Back up company tool instead. Go to the gear icon, choose Back up company, click Backup, then New Manual Backup. Pick the company, choose a backup type (Full, Incremental, or Complete), and select Request Backup. This is the one option Intuit offers that's closer to a real, restorable backup, and it's limited to the Advanced tier.
5. For anything below Advanced, look at a third-party backup app. Search the QuickBooks App Store for a backup or data-protection app built for QBO specifically. These run on a schedule and store snapshots outside QuickBooks, which is the closest a Simple Start, Essentials, or Plus subscriber gets to Desktop-style backup coverage.
6. Set a repeat reminder, whichever method you use. None of QBO's own backup options run automatically on a schedule unless a paid app is doing it for you. Put it on a calendar, weekly or monthly, so a backup actually happens instead of existing as a good intention.