The easiest and most straightforward way of heating is to immerse it in boiling water. But before you do this dont forget to remove the protective masking first.You can do this by washing the sheet in warm water,this removes all of the gelatine coating a the same time.Now,before boiling the water be sure to get all of your jigs and formers ready.These are the things that shape the perspex and you will probably find a lot of these items around the house,you can put metal spoons to good use for example,strips of perspex can be easily wound around rods,jars etc. One tip is to never boil the perspex,always boil the water first and add the perspex when the water is just off the boil,the time the perspex is left in the water depends on the thickness of the sheet but generally it is between two and ten minutes,it is ready for use when sufficently pliable to bend by itself when lifted out of the water. Take care when handling and use tongues or a similar tool,taking care not to mark or dent it while it is still soft.Wipe off all of the moisture and place the plastic in or around the shaping former. To stick perspex requires special cement called perspex cement,however if you have difficulty in finding any buy a bottle of acetone from the chemists and soak shavings or small broken pieces of perspex of perpex into it for 48 hours,this makes a very acceptable adhesive. Make sure that the product you are working with is proper perspex and not acrylic sheet an entirely different material.