How to build a 12-month rolling cash forecast for a small manufacturer?

[Isabella.H]

I run a small manufacturing business, and while we're profitable on paper, I'm constantly stressed about month-to-month liquidity. My current cash flow forecasting is basically just looking at my bank balance and upcoming invoices, which isn't giving me any real visibility or warning. I want to build a proper 12-month rolling forecast to anticipate shortfalls and plan for equipment purchases. What are the key variables I should be tracking beyond basic receivables and payables, and how do you realistically account for seasonal variations or late payments in your models? Is there a simple template or software you'd recommend for a non-accountant?