I wouldn't worry too much about it. Its more relevant if lets say you were dead set on growing specific plants like rhododendrons/azaleas/magnolias etc then you ideally need acidic soil. But for most plants I'm sure you will be fine.
But whilst your at the early stages of planning your garden then it makes sense to test your soil.
If you do create some borders, you can save yourself the effort of disposing of the dug out turf by laying it grass side down in the bottom of the border, then put the soil back on top. Or pile it in the corner of your garden (grass side to grass side) and it will turn into lovely soil by next year, that you can add back to the borders.