Simple budget for a tight month - 6 months and counting

My income is now a fraction of what it was as a marketing coordinator and I am trying to cover the essentials. I have been trying to stay organised about it. The rent is fixed and the car payment is high. Any apps or methods?

A paper list of bills by due date helped me more than an app. I could see the month at a glance.

Sell things you do not use. I made about $450 from a weekend of listing.