The importance of youth participation in the decision-making process in nation building should not be underestimated. Studies have shown that youth in marginalised communities lack opportunities for engagement in the democratic process. However, today's rapidly-advancing media technology provides an opportunity for the authorities to tackle this problem. This research investigates how participation of youth in marginalised communities can be increased through the use of media. The researchers developed an instrument to measure the participation of youth in the decision-making process via different media. This paper presents the instrumentation process and items used for such purpose. The tested instrument is called 'Measure of Media and Youth Participation in Social and Political Activities'. It consists of five sections, which are (a) Demography, (b) Media use, (c) Level of youth participation, (d) Domain of youth participation, and (e) Youth perception of media and participation.