Just covered this the other day! This is what I learned in my cost accounting class, and it made much more sense than how Becker explained it. The difference between this and Becker's tabular format is that it breaks the components into three rows and shows how they each change as you move from column to column. For variable overhead:
Actual Cost/DLH || Budgeted cost || Budgeted cost || Budgeted cost
x Actual DLH || x Actual DLH || x Budgeted DLH || x Budgeted DLH
x Act. Output || x Act. Output || x Act. Output || x Budg. Output
Spending Var. Efficiency Var. Volume Var.
I find it easiest to work right to left. As you move left, you change each amount from budgeted to actual starting at the bottom with output in the transition from the fourth column to the third column, then DLH from the third to the second, and so on. Looking at the table also helps it make intuitive sense, because if you look at the difference between the third and fourth columns, it's due solely to budgeted vs. actual output (i.e. the volume variance) and so on.
My recommendation is just to do a lot of problems using the table and pretty soon you'll be able to do it easily in your head. I found this much easier than memorizing a bunch of formulas.
One other note: the flexible budget variance is the difference between the first and third columns (the combination of the spending and efficiency variances).
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