The last step in the problem-solving process is to execute (or implement) your solution. In some cases that requires you to only convince others that the solution you’ve identified is the best one. Other times, you’ll also get to implement it, monitor its effectiveness, and take corrective actions as needed.
An essential part of the execution is to convince others to your way of seeing things, which will require you to communicate effectively. Make sure that you prepare your delivery by designing an effective presentation—including displaying information effectively and using the right type of chart; on slide design, see also here, here and here. (Design is indeed important, and not just in slides.) As you craft your message, start early, initiate with your conclusion, and consider telling it as a story.
This influencing others to see things your way may involve some negotiations. You may also need to improve your persuasion skills; one way to do so is to get your stakeholders to buy in your ideas by making them theirs.
As in all the other parts in the resolution process, enlist others to assist you; to do so, consider engaging your team and helping others be successful. Also important is for you to lead change, ensure you have the right team, and manage people optimally (see also another post on managing people). This may require you to adapt your leadership style.
If your setting allows it, you may get to solve a complex problem by building on the successful resolution of related, simpler ones.