I'm not a developer so I don't know what is required to do this, but I think it may work by simply having all wallet balances (and any other aspects of the code required to remain functional) go up in unit count by 10.

Within the software we could add a zero to the definition of base units that make up a Bitcoin, and increase all current wallet Satoshi holdings by 10. Total network value remains the same, 1 Bitcoin is still 1/21,000,000th of the whole network, we just cut the smallest pieces even smaller to increase usability. 1 Bitcoin could equal 100,000,000,000,000,000 Sats one day, or even more. It's just more division.

Right now it's not a big deal because Satoshis are only 1/10th of a cent in value, but when they grow to approach or exceed dimes and dollars I think consensus will be found to update the base chain to continue allowing ease of use, likely within a decade IMO.