David loom tie-ups

The David loom is a sinking shed jack loom, so the shafts are pulled down.

In most weaving drafts, the shaft that is raised are the shafts that are indicated in the tie up graph.
In order to see your pattern on the top surface of your weaving, you need to tie-up the white squares, not the black dots - so the opposite of a traditional jack loom pattern draft.

Weaving draft

Jack loom Tie up  Each column shows one treadle’s action. Treadle for treadle 1 must raise shafts 1-3-5-7

Tie up for David - sinking shed With the David all the shafts are already up, so you tie up the ones that must go down, so the white boxes. For treadle 1, these are the shafts 2-4-6-8

Weaving notations are getting more difficult all the time because so many publishers uses different systems. Even Interweave Press publishes one book with numbers and then the next book with black squares. This makes it hard for newer weavers.
Older books use the X‘s and O‘s. X‘s were always thought of as anchors hence they sink and O’s were thought of as balloons, hence they rise. Most Interweave Press patterns are written for rising shed looms so you will have to tie-up the blanks.