Your mind runs on the substrate of your physical brain.
You can't really improve your physical brain much. (Though you can harm it much more easily!)
You can use your brain better.
Seek out people with interesting perspectives.
Dig into surprise.
Regularly take a step back to abduct insights out of your intuition.
But the idea of your mind emerging only from your brain is limiting.
A perspective shift: seeing your mind emerge from multiple types of hardware.
The tools you use are in some way complements for your physical brain.
The line blurs as you use these tools and, like your organic brain, you fuse together.
Put another way: your wetware is only a subset of your effective brain.
In this way, you can make the substrate of your mind more powerful.
A personal knowledge management tool that you built yourself: when you add a feature, you're making your brain better!
Other ways your mind can auto-expand: viewing the internet as a part of your brain for factual retrieval.
The internet gets better on its own; your mind benefits from its increased abilities without you having to lift a finger.
Another auto-expanding thing is using LLMs to surf through artificial intuition at internet scale.