Im learning Urdu and Chinese right now but struggle to remember the characters, letters and writing systems. How can I?
I don’t know about Urdu but it’s not a great idea to use mnemonics to remember Hanzi.
Isolated Hanzi study can work, and it has worked, but it is significantly inferior to just learning it in context, because there are way too many and they have multiple meanings and readings. Learning them in context means learning vocabulary and trying to memorize whole words instead of individual characters.
If you do want to do isolated study anyway I’d recommend the book “Remembering the Hanzi”. It’s basically a structured guide based on mnemonics.
Chinese: You’re dealing with essentially the only non-alphabet-based writing system in the world. By “remember the characters”, do you mean find the right sound/pinyin for the character, the reverse, or write out the character for a particular definition?
I think you can make excellent progress through consistently reading Chinese and sounding out all of the characters, writing them/looking at them, and understanding their meaning. Go slowly and prioritize accuracy over speed. The simple characters will come after a few days (e.g. 木 mù = wood), while more sophisticated ones, which are rarer, take more time. To me, breeding familiarity with Chinese through constant exposure is the best way to improve memory.
All Chinese characters are built on a set of radicals, or small components. For example, 怒 nù, which refers to anger, is comprised of 女 (woman), 又 (again), and 心 (heart). Some of these decompositions may be a bit strange, which is why they are so memorable—you can invent your own stories once you master the radicals.
Sometimes, similar-looking characters are also pronounced similarly, though the Lipschitz constant is not small. For instance, 请 (please as an exclamation) is qǐng, while 清 (clear) is qīng. But whereas 持 (continue) is pronounced chí, 特 (special) is pronounced tè even though their right sides comprise the same two radicals: 土 (earth, tǔ) and 寸 (a little, cùn).
To summarize: Much progress can be made by working through Chinese characters one by one during ordinary reading. Then, mastering all the radicals will help you create stories for more sophisticated characters.