As a creator the next few steps happen as part of the design process, but will not be part of the final maze. They are planning steps to create a workable maze.
Step 3 (Planning step 1) - Break the trails into sections
Create sections (mine are in bubbles) which are options that can be moved to. I labeled them with letters. From the START you have 2 options to move in, into section A or into section B. If you move in direction A you will move through 4 blocks before making another decision. If you move onto B you immediately have another decision to make, D or E. When you make your sections for the first time you will make a mistake or 2. The most common mistake is including a block into a section where it does not belong. For example: If you are in A, you MUST next move to C, but C is not part of A. If you move from B to D you also MUST move to C, but C is also not part of D. C must be independent.
Notice that the bottleneck I mentioned in Step 2 is now labeled F and must be used in any solution.