Newbie trying to get better quality vocals at home. I have the gear, I just need advice on how to set up.

The space is basically open, as it is a small dining room that opens up to a larger living room and has a doorway (with no door) to a kitchen. That may itself be the problem.Terrible echo.

I have 4 corner bass traps, 3 roughly 4' by 2.5' foam squares, an SE Electronics RF-X reflection filter. How should I position them?
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Note the square above 10 ft wall is small window, wall separates kitchen from room i would like to use but doorway does not have closing door.