"Can you suggest how more tiles might be placed?"
Place a small selection of number cards on the table, together with a pile of [small hexagonal tiles]. (The square brackets indicate options for you to complete, as available.)
This is a static example. With speech and action it could be made dynamic and more simple, or difficult, according to the ability of the child.
"This shape is called 'number two' and it represents two tiles...like this, and this."
One of the intentions of Usk Tiles was that they would reinforce out-of-school learning. Instruction might better be:
"Can you place some tiles on this number to show me that you know what the number represents?"