I have included the calibration cube with no infill or top, the walls should match up to what you have set in the slicer

This is a Step extrusion multiplier test printed from 4mm to 10mm. You will need some calipers (if you have 2 this would provide a more accurate reading).the cubes rest on a 2mm base which is a good indication on the first layer squish.

Measure each step, which will help determine the extrusion multiplier required.

To work out the multiplier the formula is very straight forward take the measure it is suppose to be and divided by the measurement reading eg 3÷2.62 =1.14503186 or 1.15+/- However as Calibers can vary in measurement i would measure all 5 steps and the take the average and use that to do the extrusion multiplier.