Learning vocab is not easy and different methods work for different people. Here are just a few suggestions of ways to try...
Mind maps
I find it very effective to categorise vocab e.g. Technology. Then for each category I make a colourful mind map full of vocab. I then try to memorise the mindmap by picturing the colours.
Lucky dip
This method I love! Rip up a piece of paper and write vocab on each little piece. Try writing the word in English on one side and Spanish on the other. Then put the pieces into a small bag and pull them out individually, making yourself tranlaste the word into the language it doesn't appear in. This is great for reading / writing exams!
Flashcards
Flashcards are great for fitting a lot of information in a small amount of space. I like to choose 20 key words for an individual topic that I can fit onto one card. Flashcards are great as they're easy to carry around so you can revise on the go!