Not knowing your knowledge for music theory, I don't know if my advice will assist you in one week.
For me, memorization is a combination of two or three skills. My memorization process is as follows, I take the score to the sofa or pool where I will analyze the melody, counter melodies, structure, keys and chord progressions (use a copy because scores and pools are arch enemies). I will then go back to the piano without the score and do what I can, then go back to the pool. After several attempts I will use the score at the piano then put it away until my next session. As I lay in bed or drive a car or listen to a homily, I may run sections through my head. Eventually I can see an image of the score in my head and read it from there.
There are two other skills which are absolutely necessary; the first is a strong knowledge of music theory so you know what you are looking at. For instance, you would not be able to read unless you first learned the alphabet. Theory is the alphabet to music. Also, you will quickly recognize that all music is essentially the same once you break it down to its DNA. Secondly, I sing every note and every part. If your inner ear can hear it, and you know music theory and intervals, you will just know what the notes are and if you find you don't remember what a note or passage is, you will hear it in your mind's ear and just know what it is. For instance . . .
You probably know the song "Mary Had A Little Lamb." Sing it. Obviously it starts on the third so, using my ear and knowledge of intervals, without ever seeing the music nor having memorized it, I just know that it is:
3212333 222 355 3212333322321
This is the base secret to memorization, improvisation and transposition. Go ahead, if you know your scales, start on the third of any key and play those numbers. Poof, you can transpose. The trick now is to relearn to read numbers instead of letters.
Sure, it is more complicated with a sonata but with time, it gets easier. I played a year of weekly one hour lunch time concerts and each week memorized an hour worth of music. It was hard at first but became easier each week.
Never ever, ever, ever, ever, ever memorize by rote. You're just wasting your time. However, your arms must know where to go so basic scales, arpeggios and patters are good to know from "muscle memory." Technique, too, is in the brain. "Muscle memory" is a myth. The brain controls everything and your muscles are irrelevant.
So my three suggestions are to sing everything away from the piano, learn to read numbers instead of letters. Most of our teachers do us a disservice teaching us letters because they are absolute. Numbers are everything. I consider letter readers to be musically illiterate. Just because you can read letters and match them to a key doesn't mean you know what you are doing. Just like a dyslexic person who can speak but not read. I can drive a car but I don't have the confidence to repair it so, as a car owner, I am mechanically illiterate, but I can drive a car. Finally get a pool. Or a hot tub. Or at least a quiet place to lay down to study. WARNING, lying prostrate make cause drowsinezzz . z . . . zzzzzzzzzz