танцы с бубном

танцы с бубном or танцы с бубнами or пляски с бубном  {n. phr.}  {jokingly}  {informal}  {used by technical guys}

 {literally} tambourine dansing

A set of sophisticated and unobvious actions (for example, not clearly described in the user manual) which are necessary to be performed to achieve the particular goal (for example, in conputer set up and configuration). "Tambourine dansing" is usually a long and painful process of 'trials and errors' and can be different next time you do generally the same thing.