Just like a mogwai... Keep your accessories away from liquids.
Don't wear them in the shower or swimming or spray perfume or hairspray on them. The surface of acrylic can mar when it comes into contact with alcohol based fluids, and the glue bonding metal fixings to plastic may weaken in water.
Please be gentle with your FLI pieces. Acrylic is hard but it scratches easily. Sometimes shallow scratches can buff out with a little Brasso and a soft cloth.
Sometimes accidents happen.
Acrylic will break if you drop it on a hard surface. Please avoid this... but sometimes stuff happens! The best glue to use to repair acrylic is a product such as UHU All Plastics glue. Take care not to get this on the outer surface of the piece as it will permanently mar the acrylic. Many people also use E6000 but I find the bond is not secure and will eventually wobble loose over time. E6000 is great for reattaching brooch and earring backings back on to acrylic though.