The process of electroplating of non-conductive polymeric substrates is a serious challenge because they are not conductive. This paper shows the design and construction of a personalized electroplating apparatus and a process organization to selectively metallize 3D-printed polymer materials to enhance their mechanical and electrical characteristics. A Taguchi L16 orthogonal array Design of Experiments (DOE) 3-factor, 4-level has been used to determine the influence of current, plating time, and conductive graphite layers thickness on the plating thickness and electrical resistance. Analysis of Variance (ANOVA) has been conducted on the experimental results in order to ascertain the contribution and significance of each process parameter. Multi-criteria optimization has been carried out through order preference by similarity to ideal solution Technique (TOPSIS) whereby the weights of the criteria were assigned objectively through entropy weighting method. The optimal values of the parameters were determined to operate electroplating and electric functionality at the best quality. This research proves that the combination of additive manufacturing and electroplating is a viable method to make lightweight, electro-functional polymeric composites, which allows them to potentially be used in aerospace, electronics, and other engineering fields.