First of all, it is necessary to clean the entire ceiling from old coatings. Then, using the punch, you need to dissect completely the bells. After the ceiling is cleaned and the culbings are embroidered with the ceiling, it is necessary to primed the ceiling. After the primer dries (the drying time is indicated on the container), the joints between the plates must be sealed with facade glue. Not, in no case do not use gypsum plasters for sealing. After the facade glue dries, the bells must be primed again. Cut the net strips in advance under plaster 12-15cm wide. Stick a grid over the entire length of the seams using gypsum plaster. After the joints of the slabs completely dry again, the ceiling is completely again award and you can start alignment and putty. Do everything right and avoid unnecessary problems and disappointments.