Bitcoin is pseudonymous because each of the Bitcoin transactions is recorded in the public. It opens up opportunities to find out who owns digital funds in specific wallets, but you can use mixers to protect your privacy and achieve the maximum level of anonymity.
Other than using mixer is just to use exchange, usually the money will be mixed automatically by the exchange therefore erasing the trace of transactions. Although the it's transparent ledger it's still kinda hard to identify if the owner of certain bitcoin move their asset frequently between exchange or even convert it to other alts.