KnowWhereGraph uses the S2 system for a global grid structure. This allows for a structure where RCC relations can be used to locate things within, between, overlapping, etc cells. The process of forming these relation with custom geometries is what we refer to as integration.
We provide a tool for both generating s2 cell geometries and integrating custom geometries with them. It's generally un-necessary to generate your own S2 cells because they've been generated and exist within KnowWhereGraph - and the relations can be formed in relation to those.