To secure access to Redis, users can set up an SSL-encrypted connection using stunnel, a SSL encryption wrapper that tunnels unencrypted traffic through a SSL encrypted tunnel to another server. The process involves installing and configuring stunnel on both the client and server hosts, generating a self-signed certificate for stunnel, and creating a configuration file to specify the connection settings. The client host then establishes an SSL connection with the server host using the stunnel service, encrypting traffic between them. This setup provides an additional layer of security for Redis connections, especially in cloud-based implementations where private networks may not be available.