Studies have show that language learning is 3x more effective when you can actually see the object or action of the words you are learning. After all language is only a representation, a symbol to describe the true action, concept or object.
You could learn the word “Dangan” 弾丸 which means bullet, and no matter how many times you write it down, repeat it when it comes to a week down the line you have already forgot it!
The reason is because you are not linking these words to the physical object or action they represent. You need to visually see the item to help your brains memory function link the two together.
Take a look at this image here:
This image is really powerful as your brain is not only looking at the words and trying to remember them, it is linking it to an image and making the link unconsciously in your brain.
You should try and get into the habit of this every time you learn a new piece of vocabulary. It will really help.
Also when you learn a new sentence this can be a really powerful way to even remember something as complex as a full sentence.
For example you could say リンゴを食べ切った I finished the full apple
If you were struggling to remember this grammar pattern you should try and find an image of someone who is holding an apple core and this would unconsciously link the sentence and it’s true meaning together in your mind.
If you cant find an image, concentrate hard on what that looks like in your mind. Although a real image works best you can substitute this in your head with a visual image.
If you start to use this technique you don’t want to overload your brain with too many images in a short period of time. Focus on looking at 5 per day and see how your memory deals with that amount.
After a while you should be able to increase the amount and add more and more visual links daily.
Also, if you are a bit of a creative, you can try and draw out the meaning, this will act in the same way as looking at a picture and could potentially be even more powerful than just looking at an image.
On the flip side of this technique another good revision tip would be to look through photos of everything and anything (within reason) and try and name what you see. This would link you current vocabulary together with their physical actions of manifestations and allow you to retain them better in your mind.
You may find yourself learning vocabulary that you would never use in your life, but as some of these words are important to know for reading and specific situations you should apply extra effort to link these to something as you may not use them in a long while.