Not pretending, the most frustrating thing at the end of the year isn't profit or loss, but that you simply can't gather all your transaction records... My current habit is very old-fashioned: for every deposit, withdrawal, large on-chain transfer, cross-chain transaction, or airdrop, I immediately record a line with "time - address - txhash - purpose," and casually upload a screenshot to the cloud. On the exchange side, I just export a statement once a month, instead of waiting for it to be redesigned or the API to be deprecated.

Recently, that main public chain has been undergoing upgrades and maintenance, and everyone in the group is guessing whether the project will migrate. I instead marked those on-chain activities from those days separately: the most likely to miss a transaction before and after a fork, and if it doesn't match later, I have to guess—it's too frustrating. The principle is simple: make sure my future self can understand what I was doing at that time.