Abstract-In the era of big data, for science gateways (SG) and cyberinfrastructure (CI) projects to have the greatest impacts, the tools need to be widely adopted in the scientific community. However, diffusion activities (community engagement to spread the tools) are often an afterthought in some SG/CI projects. We warn against the fallacy of 'If You Build It, They Will Come'. Projects could be intentional in promoting tool adoption. We identified five external communication practices based on an analysis of 20 interviews with administrators, developers, users, and outreach educators working in CI across the US. The practices include raising awareness of the innovations, engaging in educational outreach, building relationships with trust, networking with the community, and keeping a track record of persistent documentations. While exploratory in nature, the findings can be used as a guideline for project to promote SG/CI diffusion. The paper serves as evidence to justify a bigger budget from funder for diffusion activities to increase adoption and broader impacts.