Researching the user's needs, and pain points are at the top of the list, followed by a competitive analysis to keep the good ideas and discard the bad ones others have used.
Teamwork allows us to see problems from multiple viewpoints helps to ensure the best solution is reached. Everyone's contribution is valuable.
Next step typically starts the design process. This where a rough draft of possible solutions to user problems is explored, critiqued, and sometimes advanced into a working prototype, guaranteeing each screen flow will work as planned. This also helps give developers a chance to visually see how each interaction works sequentially.
Testing to see how users actually respond is the most important part of this process. If the user struggles to understand how to use the design to accomplish a given task, then the design is bad and a better solution must be found. Creating designs that are intuitive is the very essence of 'user experience'.
If testing proves successful after testing the new iterations, then it is almost time to launch. As a designer it is important to add the final polishing touches on the visual designs and make sure each screen is pixel perfect. I like to provide a styling guide and redlines, if necessary, so developers will have an easy time integrating the final mock-ups to code without unnecessary frustrations.