How do I budget effectively when income arrives at irregular intervals rather than a fixed monthly salary?

How do I budget effectively when income arrives at irregular intervals rather than a fixed monthly salary? I'm trying to maintain a consistent monthly budget, but my income doesn't follow a predictable schedule — some months I earn more, some months less, and payments often arrive mid-month or late. Most budgeting advice assumes a fixed monthly paycheck, but that doesn't apply to me. I've tried: Budgeting based on last month's income Setting a "baseline" minimum income and ignoring anything above it Rolling surplus from good months into a buffer account My questions: What's the most reliable framework for budgeting with variable income? How do I decide which expense categories to prioritize when a lean month hits? Is there a standard way to define a "budget period" that isn't calendar-month, if income doesn't align with it?