The acronym SIFT reminds you to stop to evaluate if the site is reliable - are you familiar with the source? Are they generally reputable (The New York Times, Vogue, etc.)? If you aren't sure if the source is reliable, investigate the source. Who is the author? What are their credentials? Next, find trusted coverage. See if other sites are sharing the same information and if it represents a consensus viewpoint. Finally, trace claims, quotes, and media back to the original. This is important because information can be taken out of context and used in ways the original source did not intend (for help tracing images back to their source, see the "Evaluating Images" tab to the left).
If you have opinions about what you're researching, you're more likely to seek out sources that confirm your existing views on the topic.
It's important to keep your biases in mind when you are looking for information. Explicit bias relates to beliefs that you consciously hold; implicit bias is about unconscious beliefs. Everyone has implicit biases, but being aware of them is the first step to fighting bias. Uncover your implicit biases with quizzes from Harvard's Project Implicit.
How to Detect Bias in News Media - Designed specifically for evaluating bias in news sources but also applicable to other types of websites, this site suggests things to consider when looking at a website.