You need to ask yourself what you are trying to answer and the goal in conducting user testing.

What features should I include in my design?
Card Sort: Ask people what they want to see on a website or app to understand how they want to see information and what is most important to them
 

Which design will stand out better?
A/B Test: Discover which version of a design delivers the right message and appeals to your customers

Who is my target market?
Focus Group: Find out where you fit in the market and the types of people most likely to turn into paying customers

How can I differentiate my company?
User Testing: Learn where there are holes in customer needs and where you can fill that gap to provide value and stand-out opportunity areas

How do I stack up against competitors?
Benchmarking: Identify where you currently stand next to your competitors and what you can improve to get ahead

Where do people click?
First Click Test: Know if the feature or call to action is sticking-out to your users by knowing where they click and what they are drawn to
 

Can people find what they need?
Eye Tracking: See what your users sees and understand what is captivating users attention and where they may get lost

Why are people abandoning my website/app?
Usability Testing: Understand how people interact with your service, where they lose interest and why they don’t come back

Are customers happy with this?
Emotion Tracking: See how customers feel when they interact with your product or service to see the high and low points of their experience

Would people recommend me to others?
Survey: Gauge customer loyalty, satisfaction and where you can improve customers experiences to become a brand people want to tell others about