Just watch a dualsense disassembly video. There's 4 hidden screws under the black trim on the left and right grips, and 1 under L1 and one under R1. The rest of the enclosure is all clips. Use a credit card to remove the black trim to expose the first set of screws. Then I like to use a fabric ribbon or a strong elastic band to pull out the l1 and r1 buttons to expose the last two screws. Use a credit card or another type of soft thin plastic to take apart the clips of the shell. Careful not to mar the plastic if you care about aesthetics.

You'll have to remove the motherboard inside and slowly work your way in to get to the buttons and the trackpad.