The viable plate count gives a quantitative idea about the presence of microorganisms in a sample. The count actually represent the number of colony forming unit (cfu) per g ( or per mL) of the sample. The viable plate count is achieved by plating dilution of the culture until 30-35 colony exists in a single plate. We have to make dilution in such a way that the numbers of colonies in the plate never exceed 35, otherwise counting would be difficult.

what is the best medium ? use pour or spread plate ??

I think, use pour is better.