For a previous piece I made some teacups and saucers from everyday tangible materials such as cello tape, masking tape, cling film, regular household gloss paint and a sharpie marker pen.
Choose the object or shape that you would like to recreate.
Cover the whole object in cling film very tightly and into each nook. The closer and tighter the cling film the better the final outcome will be.
Cover the cling filmed object with strips of cello tape. Keep the tape close and tight around all the areas of the objects especially with unusual shaped things like the cup I have done.
Find an even area of the object to very carefully slice through the tape and cling film with a craft knife.
Take off the pieces from the object inside so you have two free standing hollow pieces like below.
Use small strips of cello tape to join these hollow pieces back together.
The new object can now be decorated however you want.