This guide describes the WB-DEGS application of the algorithm [1]; this last allows the selection of differentially expressed (DE) genes from a set of microarray experiences. The WB-DEGS aims to improve the specification of the selection process and minimize the background noise by setting thresholds of Fold Change (FC) and P_values the between conditions. The proposed algorithm is implemented as an application in the free R / Bioconductor software.