So  here is how my brain works to memorize this test:

 

-Canter In, Halt, Salute at X, trot off, turn left (to me, this entire sequence is one "bullet point" and one movement, so that's why I group it like that)

-Medium diagonal, 6-7 steps collected over X (alternatively, I've also said "medium, collect, medium" as I know it is the full diagonal)

-Half pass to X, half pass back to corner (I've also said "half pass in and back out")

-Extended diagonal

-Shoulder in, turn, turn, shoulder in (as I already know we do it halfway and then change directions and do it the other half)

-Walk C

-Turn right M, pirouette right, pirouette left, turn left

-Extended middle diagonal

-Canter corner

-Centerline, half pass to middle, flying change corner

-Circle 20m C, collect 5-6 strides between quarterlines

-Medium longside

-Centerline, half pass to middle, flying change corner

-Extended longside

-Flying changes quarterline, centerline, quarterline

-Trot out of corner (i.e. coming out of the short side)

-Middle turn, turn, halt at judge. (i.e. at G, otherwise I would've termed it differently)

 

That is basically what is going on in my head as I ride the test as well. The shorter description, the better and easier you will memorize and remember.

 

You may also notice that I didn't specifically include back to collected gaits after any sort of medium/extended. That is because in my head, collected gaits are the default, as you can see by the test. The mediums and extendeds are additional to the test, then you return to the default.

 

You may also note that I left off some other items. For example, I just say "diagonal" and "longside" for all of my trot and canter mediums/extendeds. That is because in my head, I already know the entire test only has full longsides and diagonals for all of the mediums and extendeds (minus the walk). Therefore I just need to remember all trot/canter mediums/extendeds are full diagonals, I don't need to repeat it each time and take up brain space. I also view full longsides and full diagonals as the "default", so I only make a specific note if they are partial.

 

Hopefully this walkthrough was informative. It may be a lot to read, but I think if you take this practice and transfer it to your own dressage test at your level of choosing, you'll find that it makes memorizing the test much easier! Give it a try and let me know how it goes!