How do I change my DPI on my phone?

I'm curious, could you please elaborate on the process of adjusting the DPI, or dots per inch, setting on a smartphone? I'm looking to optimize the display for my personal preference and would appreciate a step-by-step guide on how to navigate through the settings to make this change. Is there a specific application or tool required, or can it be done directly through the phone's native settings? Additionally, are there any potential risks or considerations I should be aware of before making this adjustment?