Once a month. Once a month, with no intention to go more frequently? Just give up, pack it in and go home.
We live in a world where it’s not just “best practice”, but it’s actually easy to deploy code multiple times per day. This garners you opportunities to learn from your customers, multiple times per day.
A few pointers to get you going in the right direction: Unit Tests, GitHub Flow, Test Automation, CI/CD, Microservices, Feature Flags, New Relic, Chat Ops.