Those sets of wallstickers are produced from self-adhesive vinyl and cut to the shapes seen in the picture above.
They are place on stencils that measures 30 cm x 30 cm. On every stencil there is a certain number of pieces that you just peel from the paper and apply on the wall. They can be applied to almost any smooth, flat surface – e.g. walls, mirrors, doors – and easily removed in most cases.
Please remember to clean the wall from any dirt or dust before application.