Can your cushion support a drink?
Check compression, seams and the way the seat moves.
Press where the drink would sit
With no drink present, press around the intended spot. If the surface slopes, folds or sinks as you sit, choose a separate table rather than relying on the holder to correct it.
Leave the joins clear
A stitched seam or gap between cushions can leave part of the base unsupported. The complete 5.2-inch footprint needs one supported, level resting area.
Plan for people moving
Keep the drink outside the space used to sit, turn or stand. A level empty seat can change shape under a person or pet.