How do I compare two sources?

There are lots of different things to consider when looking at sources: first you want to read through them, and look at the authorship and date, as that will give you some clues as to any differences you spot between them. They might be in different forms - you'd want to consider why that was, and how that affects the source. They'll probably take a different view on the central theme which both are addressing, and you should both note that and consider why that might be. They might also discuss events in different tones, which you can again explain via their authorship, the date when they were written, or the form in which the content is presented. Remember to use your own knowledge, so you can compare what's said in the sources to what you know actually happened: why might the sources differ from the facts?