Baffled by baffles

What do you make baffles out of?
Where do you place them?
How do you make them stay put in the tube?

I'm thinking that heavy black cardstock or a circle of black plastic should do for my new contraption.

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last set I made for a 10 inch DOB had the disks cut from cardboard and sprayed flat black. I was three flat pieces of wood trim to space the disks and wire tie them in place Kinda like a truss system. Flock will work just as good and is easier. For a scope that small you could get that peel and stick window insulation in different thickness and layer to close dimensions.

Good luck Dave