First of all, you need to decide what you want to find out. This is your research topic, and should be something that you can answer through your dissertation. When you draft this, talk to your tutors and ask them what they think - they'll know what could be realistic and acheivable. You might also find it useful to do some exploratory reading and find out what has already been written on your area of interest.
Once you have a topic, you can develop potential research questions. This establishes what you want to find out and should be something that you can answer through your dissertation. Use post-it notes to think of different ways to describe your most important words (also known as key concepts or keywords), or use the downloadable worksheet below. That will get you ready for step 2!
Once you have a research question in mind, try mind-mapping to identify related questions and gaps in your knowledge.
When deciding on a topic, choosing what not to include is just as important! Consider how you will limit your research.
Picking out the keywords from your research question will help you search Summon and other scholarly databases in an efficient way. This video gives advice on selecting keywords, and also considering synonyms when you search.