How do I provide AWS credentials to Kubernetes?

I'm setting up a Kubernetes cluster on AWS and as part of the configuration for say the API Server, I provide the --cloud-provider=aws setting.

Once it starts up, however, I see in the logs that it complains about not having AWS credentials: NoCredentialProviders: no valid providers in chain

After some searching, it seems that this issue was resolved for most people by using the "kube-up" script. However, for those who are not using the script to set up their cluster, how do we provide Kubernetes with AWS credentials?