Here is a small bit about preparation for an English welt with beveled waist:
Insole “blocked” to the last. I use a combination of nails and stretch medical bandage to snug the leather to the last.
Cut to shape
Cut the channels for the holdfast
Then carve out around the holdfast
and finally I prefer to pre-punch the holes in the insole before I last the upper. It is not necessary but it gives me a more even stitch.