How do I choose a strong dissertation topic for my Data Science BSc and stand out ?

I'm a third-year BSc Honours student in Data Science and Systems, about to start my final year. My dissertation is coming up soon and I don't know much about the process yet. What is a dissertation, how do I pick a good topic, and what factors to consider when choosing one. How do I approach the whole project so my work is outstanding.

Any guidance from people who've been through a dissertation (in data science or a related field) would really help. Thank you!