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It's a tricky art. It's helpful to learn some of the basics such as how variables are passed to a function on the stack for x86 or as registers with x64. Beyond that it takes practice. Things that have helped me are writing c code and dissassembling it, stepping through code with GDB and working on crackmes and CTFs.

For radare2 in particular, this tutorial was helpful: https://leotindall.com/tutorial/an-intro-to-x86_64-reverse-e...

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Yeah, writing simple C programs using various constructs (switch/if/for statements, structs, different APIs, etc.) and then looking at the produced assembly is a good way to learn.

Another thing I like to do is to rewrite complex parts of the disassembly in pseudo-C (though radare has an option to do this automatically), which makes the overall logic easier to see (and is, of course, the entire point of decompilers like Hex-Rays).

This works. Be sure to try different compilers and optimization levels.

You can become a better programmer this way. You start to get a real feel for what the compiler can and can't optimize. For example, you can see how a do...while loop is usually the best kind of loop, but without seeing the assembly you might assume they are all the same.

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