How to create a new Plugin in Bpmn.io?

We want to create a plugin for bpmn-js which can help to convert the bpmn diagram to be exported to neo4j database and represent the diagram as nodes and relationships. We want create a button inside the bpmn editor itself, from where all the data in the diagram are to be sent directly to neo4j database.
Can you provide the steps to apply the feature directly?

@arnab We cannot assist you directly with custom feature development. We’re happy to answer your concrete questions though.