Every time a WooCommerce update comes out the network of weeping and wailing is filled because this or that thing has stopped working, or because a store has gone directly to hell, and it's your fault, you know .
If your store stops working after updating WooCommerce it's your fault
Yes, it's your fault because as responsible for the maintenance of the online store you should have done tests before applying any update .
Something that is required in any web, try before updating, in an eCommerce is absolutely imperative since every minute that the online store is down you are losing sales that you could be doing, and customers that may not come back .
Betas exist for something . In fact they exist so that you prove if your web / shop will be compatible with the new version, before the definitive version comes out, and of step so that you warn if you see any failure in your concrete installation.
Keep in mind that l developers can not know what configuration, plugins, theme, customizations, each store has so it is impossible that each new version does not break something, it is statistically impossible.
So is your only responsibility as store manager, update with network, knowing in advance that nothing will break.
How do you test WooCommerce betas?
The best method is download and install the WooCommerce Beta Tester plugin which allows you to upgrade to beta and RC versions, and then try everything before the final version comes out.
Ideally, install it on a most accurate copy possible to your store rea l, and dedicate a time after each new preliminary version, in case you have to warn the developer of your theme / plugins that something will not work.
What the plugin does is allow you update your stable version of WooCommerce to the latest beta or RC versions available in the official GitHub repository on WooCommerce .
How is WooCommerce updated correctly to not break anything?
 Well, finally the right question.
Doing tests, as you could imagine. Test every new beta, test everything, check everything, before updating the actual store.
How do I test WooCommerce before upgrading?
The steps are simpler than you can imagine.
Wait a week
Do not be a guinea pig for the rest of the planet. Before suffering errors in your flesh learn from others .
It is quite common for a few days after an update to get another one that solves the most common common mistakes, and that will save you time and dislikes
When you start your tests you will have already saved yourself a few mistakes.
The only situation where it would be better to start testing to update without waiting is if the update includes important security patches . It is better to work a little more than to have a fat dislike for a serious security vulnerability.
Before dealing with anything else, the first thing is always to make a full backup of your store in a safe place. Either from the panel of your hosting or with your favorite plugin, make sure the copy will work if you need to restore your store from it.
Make a copy of your online store
You should always have one exact copy of your online store with the same plugins, themes and versions of everything, even with the same content, images, orders, from your real store.
You can make this copy in many ways, I propose these 3 alternatives :
Make a manual copy
Export all the contents of your store ( Tools> Export ) and create a new installation of WordPress in a folder or subdomain of your server.
There you install the same version of WordPress, theme and plugins, import the previously exported content and start doing tests.
Make an automatic clone
If you have cPanel ] make a clone of your store. It is a very fast process, and you will have an exact copy of your online store in a folder or subdomain of your choice.
Go to the Softaculous application and, in the list of sites, click on the make copies icon: 
In the next screen you are asked in which folder, domain or subdomain you want to make the copy and all you have to do is click on the clone installation button.
The clone is Exactly, with everything just like your real store, and you enter with your same credentials.
Create a copy in staging
Make a copy of essays, or staging of your store The best hosting providers such as SiteGround offer this functionality.
An exact copy of your store will be created in which to test. You can protect the copy with a password to prevent its display if you prefer.
And when you finish you can make the copy, once everything works, becomes your real store.
The latter is the best option by far because when you finish doing tests you just have to launch the copy to replace the real store (remember to always make a backup) and you will have done all the Checks
What tests do I do in my online store before updating WooCommerce?
It sounds to me like something I said before, right?
TRY IT ALL!
What I recommend is the following sequence of 15 base steps which is the one that I use with my clients:
Empty and deactivates all the caches (server, web, browsers) and you can start …
- Activa el regi debugger to see any possible execution error during the tests.
- Update WooCommerce and any other plugin or theme that you have pending to update. One thing at a time
- Check any execution errors on ALL the pages of your store (product, categories, user account, cart, finalize purchase, cover, etc).
- Check that all the links work (type ) and store buttons (Add to cart, Finish purchase, Apply coupon, Sign up, Sign in, etc)
- Test with different user profiles, not just administrator.
- Make real purchases of products with all the payment gateways, do not trust the test modes or sandbox because sometimes a gateway will work in test mode but it can give live problems, and what matters is that the money between in the account, right? In passing apply discount coupons (99% if you want) to prove they work.
- Check that all the emails that your store should send arrive.
- Check that the money goes into your Paypal, Stripe, banks.  Check that downloads of products with download work.
- Check that inventory is updated correctly.
- Make a refund with each compatible payment gateway.
- If you have an affiliate system, check that the correct uploads are made. commissions.
- Check that subscriptions work if you have membership products.
- Check that reservations work if you have products of this type.
- Check that all the plugins work and do what they're supposed to do
When you're finished, turn off the debug log and activate the caches.
If everything went well, back up your store if you did not do it before, and you can to perform the same sequence of tests in the real store . It does not matter what method is chosen for the copy.
I know it may sound exaggerated, when you've already tried everything in the copy, but experience has taught me that because something works once it does not have to always work.