When mixing the wet and dry together to make the dough, you want it to be soft and slightly sticky but not soggy. Add a little more milk if it is too dry, or a little more flour if too wet and sticky.
The dough should not be completely mixed and smooth, but more of a shaggy dough, when tipped out. This allows the last bit of the dough to be brought together and not overworked.
No need for a rolling pin to flatten the dough: simply using your fingers to even out the dough is perfect!
It is really important not to twist the cutter when stamping out the scones. Twisting the cutter seals the sides of the scone, hindering the rise and so the beautiful shape you can achieve. Straight down and back up again is perfect, and make sure to flour the cutter between each cut.
Put the cut scones close together to bake if you prefer softer scones. Spacing them further apart will give more browned and crisper scones. It's all about personal preference!
When brushing with milk, be very careful to only brush the tops of the scones. If milk drips down the sides, it can hinder the rise of the scones, so you could end up with lopsided rising, but still delicious scones!