Well, I'm not sure what symptoms of dyscalculia you specifically struggle with, but knowing which areas you need to work on would be a good starting point.

For me, I struggled with dyscalculia throughout school, but now as an adult, I have trained myself to do mental math.

I tried a lot of different methods of learning math, and it included lots of sensory methods, mostly things that were more "hands on," like colors, shapes, something that I could hold and manipulate.

There's methods of math using your hands, not only to count to ten. Depending on the method, you could use it as an abacus, sign language, binary numbers, the times tables.

Then there's some ancient arithmatic, like by using the abacus and vedic math. There are videos of kids doing insanely fast number calculations by using these ancient methods.

There's also methods of using colors for each number. The Human Calculator Scott Flansburg imagines a number grid in his mind, so that he can calculate things quickly.

And there's a lot more things, but these were the interesting ones that I remember.

Anyways, I hope you become the next Albert Einstein one day!

Well I was still counting with my fingers in my early 20s, so instead of shaming myself over it, because there's people who would shame me for it, I got fed up at all the people in my life who ever told me to stop counting with my fingers, and I decided that if I was going to count with my fingers for the rest of my life, I might as well learn different methods of doing just that. Everyone uses their hands for daily work and tasks, so I thought why is it shameful for me to learn math using my hands? So that's where I started.

Also, I realized that the school's way of learning math just didn't work for me, I mean it might work for others, so that's great for them, but I needed to find another way that works for me.

At the beginning, numbers just made me anxious and panicked, but I kept my eyes on the numbers, I kept staring at the patterns even through the fear, until my mind started making sense of it, and the fear was replaced by understanding.

So after a few years of curiosity and discovering different ways of doing math, I was eventually able to do mental math, which shocked me, because I never thought I'd be able to do that in my entire lifetime.

I also used Khan Academy, and started with kindergarden math, and then I went up by grade level. The courses are free. This is more like the structured and boring math in school, but it showed me how much of school math that I could get through.

Anyways, just make a game out of anything you want to learn, and then you can learn anything you want to.

to do it in your head? multiplication alone past multiplying 3-digit numbers is cumbersome

but there are numerous compensatory methods:

knuckles

pen and paper

quipu

and more modern - calculator :D

I've never bothered with trying to do more then multiplying 3-digit numbers because it takes time and it is prone to mistakes, so it is not a prudent method,