When you dump the dough onto a lightly floured surface and it's still sticky, gradually add flour and keep kneading the dough with dusted hands. Keep in mind that the texture of scone dough should be a little wet and sticky as this texture will help produce the lightest, fluffiest texture once baked.  Also, do not knead the dough too much. Knead only till everything comes together and then stop, or you will lose those air pockets.