MongoDB has provided some useful tips for in MongoDB Atlas, including the following:

• Use the latest version of MongoDB whenever possible.
• Use the latest Transport Layer Security (TLS) version available, which is 1.3 at the time of writing.
• Encryption at rest cannot be used together with continuous backups. We need to select cloud provider snapshots to be able to use this feature.
• It's probably a good idea to disable server-side JavaScript, unless we know why we need it, for example, when we have legacy MapReduce jobs in place.
• Requiring indexes for all queries can be useful if we have a well-defined business case and requirements for how we will use the database, and/or we expect our dataset to be so large that querying without indexes is practically impossible.
• Finally, we get to select the name of our cluster. This cannot be changed after creation so it's important to agree with fellow team members before we click on the Create Cluster button.

After a bit of waiting, our cluster will be operational, and we will be able to connect to it via a plain old MongoDB URI.