Have you dabbed boards on before?
Its not particularly difficult although there is a knack and learning curve to it. Getting the boards flat and plumb is half the battle. I usually do my own boarding before tiling, but had to get over a badly boarded wall recently that i would have usually just ripped off and started again. Not possible in this instance, so had to spend time levelling out with rapid set and going up a notch size. No fun 🙁