This manual has a twofold aim: to present the WeightedCluster library and offer a step-by-step guide to creating typologies of sequences for the social sciences. In particular, this library makes it possible to represent graphically the results of a hierarchical cluster analysis, to group identical sequences in order to analyse a larger number of sequences, to compute a set of measures of partition quality and also an optimized PAM (Partitioning Around Medoids) algorithm taking account of weightings. The library also offers procedures to facilitate the choice of a particular clustering solution and to choose the optimal number of groups. In addition to the methods, we also discuss the building of typologies of sequences in the social sciences and the assumptions underlying this operation. In particular we clarify the place that should be given to the creation of typologies in the analysis of sequences. We thus show that these methods offer an important descriptive point of view on sequences by bringing to light recurrent patterns. However, they should not be used in a confirmatory analysis, since they can point to misleading conclusions.