I am about to lay decking and azek trim and have a few questions.Our house is L-shaped with the deck attached on two sides.

1)When I picture frame the decking do I continue pictiure frame around entire deck or only outside edges

2) I would like to picture frame stair treads what is common procedure for this

3) what order is best for stairs to be finished. ( risers with Azek than treads or treads than Azek risers).

4) do I start with trim on outside of stringers first.

Thanks in advance

any pics or links would be awesome