Do not keep anything on top of the brooch as the varnish may take on the pattern of the object.
This can sometimes be repaired – the varnish bounces back on its own – but best to avoid.
This is a piece of art. Just like you wouldn’t sit on a painting, scratch it on purpose or try to bend it, use similar care with this piece.
Ideally, store flat in a good quality plastic cover. Plastic does not stick to varnish / acrylics.
Keep away from things like isopropyl alcohol / perfume and even oily make up.
Excessive heat or cold are best avoided.
If it gets dusty / linty, wipe gently with soft cloth.