If you want to break a chain of transactions (separate inputs from outputs), you can use VPN+TOR and a reputable mixer, or a non-KYC exchange. Personally, I'm looking forward to a Dandelion-capable wallet that obfuscates propagation. TOR browser is ideal where possible, as browsers leak lots of PII to third party services.

Coin selection is really important if you want to avoid being linked to previous transactions. I avoid letting wallets send by default, and instead select inputs based on their history and destination. When I need to consolidate inputs, I might break the chain of transactions to obfuscate the original source.

Another thing to keep in mind is how lightweight wallets work. Electrum is awesome for its usability and fast syncing, but if you connect to servers at random, the way it queries transactions can theoretically allow snooping third parties to link your wallet addresses together. Ideally, you'd run a Core node as an Electrum server, then connect to that.