You can evaluate any source using the 5 W's:
When you see a claim that may not be 100% true, there are four steps, called "moves," you can take to fact-check the claim. If you successfully confirm a fact at any stage, you can stop - it's not always necessary to complete all four moves.
In addition to the fact-checking moves, you should also develop one new habit:
The habit is simple. When you feel strong emotion – happiness, anger, pride, vindication – in response to a claim, STOP. Above all, these are the claims that you must fact-check.
Why? Because our emotions tend to override our ability to reason. It's important to learn to recognize when this is happening, so you can approach important issues with a more analytical frame of mind.
The information above is based on the following work by Michael A. Caulfield:
A freely-available ebook that takes you step-by-step through the fact-checking process.