A place for diyas away from moving fabric
The surrounding space matters as much as the holder when placing a lit diya.

A diya is easy to place where it looks balanced in a display. It is harder to notice the curtain that can move towards it, the sleeve that will pass over it or the edge of a table that a child can reach. Look at the arrangement as a route through the room, not only as a still picture.
Choose a stable, heat-resistant holder on a stable surface. Keep the flame away from fabrics, paper decorations and anything else that can catch fire. A broad decorative tray is not automatically heat-resistant, and a crowded tray can bring combustible decorations too close to the flame.
Leave room for people
Avoid putting a lit diya where someone must lean across it to reach food, a switch or another object. Floor-level displays need particular care because hems, bags, children and pets can pass close by. An entrance that becomes crowded when guests arrive is a different environment from the empty doorway where you arranged the display.
Keep lit diyas attended and extinguish them before leaving the room or sleeping. Follow the holder's instructions and allow it to cool before handling or storing it. Do not refill a hot or lit lamp. If the placement cannot be supervised comfortably, use an appropriate flameless alternative instead.
The London Fire Brigade's Diwali advice is useful for these basic flame precautions, even though the setting of your celebration may be different. It emphasises stable placement, distance from combustible material and supervision. Decoration should leave those conditions possible throughout the evening.
Separate the display from storage
Keep spare oil and unused decorations away from the live flame. Set aside a clear place for cooled holders afterwards rather than leaving them among paper wrapping or cloth. Clean and dry each holder according to its material before packing it away.
When choosing new holders, consider how you will lift and clean them as well as their appearance. A design that traps residue in narrow recesses may be inconvenient for repeated use. For a gift, include the supplied instructions and avoid implying that a decorative object can safely hold a flame unless it is actually designed for that purpose.