Choose a tray for order
A shallow tray is the default when the job has washers, plastic clips, mixed fastener sizes, or a sequence you need to preserve. Dividers or paper labels help prevent reassembly mistakes. A tray also works when you are seated at a bench.
Choose a mat for layout
A flat mat gives room to place components in a diagram-like pattern. It is useful when the surface is stable and you need to see where each part came from. A mat is less useful if the work moves from room to room.
Consider a wristband for reach
A wristband may reduce trips to the tray for compatible metal fasteners during a repetitive task. It does not replace a parts map or safe tool handling. Check the manufacturer's fit and material details, and keep magnets away from items where the device maker advises against them.