Circurlar needles transferred to DPNs

OK feel free to link in other forum posts, I just can’t seem to find what I"m looking for…
I’m knitting in the round and decreasing down (top of a hat). At what point to I transfer to DPNs? Already I feel like the stitches are stretched on the existing cable.
Then HOW do I transfer to the DPNs? The videos assume you cast-on onto DPNs… do I just consider the circular needle one straight needle for transfer purposes?
This is my first time trying to knit down to the top of a hat (or anything for that matter) and conceptually I’m not seeing how I get down to 0 stitches that perfectly end in the top of a hat with no holes AGGGHHHHHH
So thanks for any help!

If the stitches are getting tight on the circ needle, now is a good time to switch.

Just pick up one of the dbl pts in your right hand, circ in your left hand and start knitting onto the dbl pt. Work about 1/4 of the total stitches. then pick up a new dbl pt and work the next 1/4 of stitches. repeat with the 3rd and 4th dbl pt needle. (I am assuming you have 5 total dbl pts. If you one have 4, work 1/3 of the total stitches onto 3 of the needles).

Or if it is too tight to knit onto the DPNs you can just slide them over. Just divy up the sts into the three needles and then begin knitting with the DPNs.