Remove Personalization
By default, Reddit personalizes its advertisements to your behavior. More concerningly, some of this content comes from third parties, such as tracking cookies or site widgets. If you have a Reddit account, you can opt out of all these options at reddit.com/personalization.
Change your visibility
Reddit has settings to adjust who can follow you and what kind of data about you is shown on your profile. This can make it much easier to track you, but luckily you can disable a lot of functionality in your account settings.
Enable Two-Factor Authentication
You might not think your Reddit account contains anything sensitive, but attackers regularly target Reddit accounts with leaked password lists in order to boost their submissions.
To enable two-factor authentication, go to the bottom of https://www.reddit.com/settings/privacy and click on the bottom panel.
You will need to use an authenticator app on your phone to scan the resulting QR code.
Reddit does occassionally send alerts on usual activity, so if you have ever received one of the below notices in your email, you would be a great candidate for two factor authentication.
Limit Application Access
If you look at https://reddit.com/prefs/apps, you can see a list of all the applications you have permitted to access your Reddit account. While it’s ok to connect your Reddit account to applications from trusted developers, you should periodically review access. If you are no longer using that application you tested out, it’s a best practice to revoke its access. A vulnerability in any of these applications represents a potential attack vector for your Reddit account.
Limit your Information
Reddit is a place for discussion, but comments are a perfect way to mine data about your location, family history, interests, or other sensitive information. To get a sense for what someone can figure out about you, try using a Reddit analysis tool such as https://redditmetis.com
In order to protect your privacy, consider creating a new profile every few months. If karma is a concern, try the Power Delete Suite to overwrite then delete your comments. You can also turn off search engine indexing in your privacy and security settings to ensure Google’s cache isn’t saving your profile. While third party sites may still make mirrors of Reddit content, this can greatly limit your exposure.
Use a Strong Password
Reddit’s password policy allows you to make simple 6 character passwords. Use a strong, unique password.