In my post on Malwares, we discussed the relative importance of malwares. In the analogy, I described a hacker as a door specialist and a scammer as a burglar. So many of the tools the burglar (scammer) use are malwares. Taking the most basic approach, I would say the best way to keep scammers at bay is being vigilant and password security is very important.
The relative difficulty of bypassing a password is called password strength. Passwords that contain more than 7 characters create a milestone for hackers and thieves. And do not be mistaken, I do not mean that as long as your password contains characters more than 7 characters, you are safe. I'm only telling you that long passwords are relatively more difficult to bypass as compared to shorter ones.
Make sure that your password do not just contain a word from the dictionary: Doing so will make you susceptible to dictionary attacks. Examples of passwords that are susceptible to dictionary attacks are - ( "alienate", "courageous", "mathematics" ): These words can be found in the dictionary, making it dangerous to be used as a serious password. If you want or need to form a password that contains a word from the dictionary, care to add numbers, random characters and symbols (like: mathematics@#2167/) or applying letter casing techniques (like: "MatheMatics103&$1", "Abbr40Hrl4Noa:$1?"). No need to make things difficult for yourself; just combine and apply these techniques and make sure you can easily remember your password.
Be sure to change your password every 2-3months
And yes, don't tell me that you can't use auto-generated passwords. Auto-generated passwords are reliable but human-created ones are more difficult to crack and understand. Lastly, don't allow yourself to be manipulated or "socially engineered" it is quite annoying and frustrating. Don't be fooled.