Give professional advice, (This is a homework)

Hello, everyone. I'm from the local police station. My name is Leanne. As a police officer, I often hear of situations where a person was mugged late at night. I've been invited by the college to teach you how to avoid street crime.
There are simple steps you can take to avoid street crime.
First, you need to watch out. Beware of being too trustful of strangers who maybe are criminals.
Second, be careful of walking along dark roads late at night, especially girls. You'd better to walk together with others.
Finally, you should always keep calm under any circumstances. In this case, you'll be safe.

Obey the rules of punctuation spacing and capitalization. "Be careful to walk along dark roads," literally means that you should walk along dark roads. I think that is opposite of what you mean. Also, being calm will not protect you! The ability (or tools) to resist viciously and raise an alarm can protect you.