Start with analytical reading.
Your task is to collect high-quality literature sources, read them critically, make connections, check debatable moments, and anticipate conclusions.
Political issues are often complicated with many parties involved, so you often have to pick a side and explain your choice.
A number of Joint Honours degrees have a compulsory dissertation project, which students may opt to write either in Politics or in their other subject area.
The dissertation is 10,000 words long and may be on an empirical or theoretical topic related to Politics.