Hi there,
First off, let me assure you that many people start out in the 400s and end up scoring substantially higher. Having said that, if you have lofty score goals (650+), it's going to take a substantial effort to get there.
As for a study plan, it depends on what materials you use. I, of course, am going to recommend
Manhattan Prep, and I'm sure every other company will recommend their own materials.

The most important thing, though, is that you get hold of a comprehensive program of instruction. Don't just try to learn by doing a bunch of tests and practice problems. That won't train you to make the kind of change necessary to improve your score.
One other thing--don't get in the habit of counting your missed questions. Although those numbers are certainly a bit higher than we'd like to see, the GMAT is an adaptive test (except for IR), meaning that it gets harder as you do better. For that reason, even if you get to 700 you may miss up to 40% of the questions. It's more important to look at your score for each section and at the difficulty of questions you're missing. Missing easy questions is more of a problem than missing hard ones, and the goal is to keep moving the threshold up, so that you're performing more reliably on harder questions. Just don't expect to start getting everything right at any point--that's a goal that eludes even 99th percentile test-takers.