Take note of changes of spelling or alternative (westernized) names of important figures as you research. Many names, places, and even ideas may have had changing spellings depending on the translators who recorded them.
Look for combinations of primary and secondary sources.
Look for historical viewpoints both internal and external to the region/population of your topic.
The study of history can be varied and full of nuance. Try to approach your research from an open and relaxed viewpoint that allows you to see connections between sources and ideas as you gather them. This guide will give you some starting points; it is not intended to be an exhaustive list of research sources.