Struggling with the 'batchim' shift when speaking quickly

I've been studying Korean for a few months, and while my reading is okay, I constantly trip over batchim rules like liaison and nasalization during real-time conversation. For example, '같이' sounds like '가치', but when I try to force the correct pronunciation in a sentence, I freeze up. I need a way to integrate these sound changes into muscle memory so I don't sound robotic. How do you all practice these shifts so they become second nature rather than something I have to calculate mid-sentence?