I've picked up a handful of IT certifications while working full-time, usually one to three months each. I'm not unusually smart. I just decide how I'm going to study before I start, and that part does most of the work. Here's the method.
Set the finish line as a number
The single thing that helped most was deciding, before I ever booked the exam, the score I had to reach before I was allowed to book it.
For networking certs I'd run through a question bank several times, then switch to exam-simulation mode and keep going until my score sat around 90 to 95 percent. Only then did I register. Not "I feel about ready," but "I hit the number, so I book it." When the trigger is a number, you stop agonizing over whether you're ready.
Cap the timeline, or it never ends
