These short video demonstrates to students how to develop an appropriate topic for a research paper by considering goals, approaches, topic scope and helpful resources.
Some people find brainstorming techniques such as concept mapping to be helpful. Concept maps are linked nodes of concepts or ideas; the linking arrows demonstrate connections between nodes.
Source: “concept_map_lrg,” jean-louis zimmermann 
There are tons of different software options available to assist with concept mapping.
Here are a few browser-based tools to get you started: