Hi nik256.
To create a study plan, you need to determine a score goal and also determine what you need to accomplish to achieve that score goal.
To determine what you need to accomplish to achieve your score goal, use your official practice tests scores as indicators of how far you need to go get to your goal and also consider your weaker and stronger topics.
For example, if your score goal is 720, and your quant section score is strong, but you're weak in Geometry, then working on Geometry will have to be part of your study plan. You ccan consider other topics and how strong you are in them to decide what else to include in your study plan.
On the other hand, if you need to work on many topics to master the GMAT, then your move is likely to use a more general study plan that takes you through one topic at a time, covering all the topics that the GMAT involves.. There are many available online that you can choose from.
Alternatively, you could sign up for a self-study course that will provide a study plan, provide resources to use while following that plan, and help you track your progress and performance as you work your way through the plan.
For more on how to create a study plan that makes sense for you, see this post.
The Best Way to Study for the GMAT