COVID-19 showed the need for community support networks to help vulnerable individuals that were forced to stay in their homes during extended periods. While the pandemic is slowly passing, there is still a need for this type of help, especially for elderly who nowadays want to live longer in their own home. Several social engagement platforms are already offering support for this type of services. However, some became rather inactive, while others are successful but not always in the context of offering help to vulnerable elderly. In this paper we present 16 design recommendations to consider when designing (or to improve) social engagement platforms focused on volunteerism for helping older people. These recommendations are based on the evaluation of 10 digital social engagement platforms that allow asking for assistance and/or volunteering to provide help.