I agree with Cam - there is no shortage of applications and tools available - from paper based to desktop to mobile. You can do an easy search on google or bing to see all of those available. Many tools follow a methodology - or framework for staying organized. That's because how you think about your priorities and time management is really the most important aspect of staying organized. So, in addition to the tools, you may want to consider different workflows and priority setting frameworks for staying organized. One of the leading methodologies is called GTD - which stands for Getting Things Done by David Allen. He has many fans and followers - his books are well known and he actively teaches webinars for the devoted and disorganized. Good Luck!