I believe that User Experience design is an iterative process where all phases are connected to each other. While no two projects are alike, the actual process is rather straightforward, and can be summarized in the following five phases:
Define and Research
During this phase, key goals, insights and values are identified through interviews with stakeholders, user observations and surveys. This is mostly a data-gathering phase that helps me understand the context and requirements.
Analyze
The aim of this phase is to draw insights from data collected during the Research phase. Analysis includes making hypothetical personas and scenarios. Here I visualize the user interaction.
Communicate the Idea
During this stage, I take key concepts from sketches/wireframes and use them to create low fidelity prototypes and tangible MVPs. I use these rough prototypes to get early validation of the design direction from users and stakeholders.
Prototype and Test
Next, I create medium and high fidelity prototypes that I use for user testing in both, structured and informal settings. During this phase I perform usability and A/B testing of various design options.
Validate and Repeat
Next, I use the feedback and data I gathered from end-users and stakeholders during the Testing phase to iterate on the design. The data I gathered provides insight into how the prototype and interactions should be refined to improve the user experience.