The productivity of smallholder oil palm plantations in Indonesia remains constrained by low soil fertility resulting from heavy dependence on inorganic fertilizers, which can account for 25–30% of total production costs. Margosari Village, Seluma Regency, holds considerable potential for utilizing cattle waste as organic fertilizer through the Cattle–Oil Palm Integration System (SISKA) concept; however, this potential remains underutilized due to the community's limited knowledge of proper composting techniques. This community service activity aimed to improve local knowledge and skills in processing cattle manure into high-quality compost as an affordable and sustainable fertilization alternative. The implementation method consisted of three stages: socialization of the SISKA concept, hands-on demonstration of compost production (drying cattle manure, mixing it with rice husk, adding EM4 solution, and fermenting for 7–14 days), and a discussion and question-and-answer session. Results showed a significant improvement in participants' understanding, with post-test results indicating that all respondents (100%) understood the need to compost cattle manure before field application, compared to only 25% at pre-test. Participants were also able to identify carbon-source materials, characteristics of mature compost, and solutions for addressing foul odors in compost piles. The activity was concluded to be effective in building the independence of farmers and livestock owners in producing affordable, accessible, and environmentally friendly organic fertilizer, while also supporting reduced environmental pollution and lower oil palm production costs.