The online service of the obfuscation service can obfuscate the traceability between users by using independent bitcoin addresses to receive and return the same amount of bitcoins. It should be noted that the legality of using such services may vary in different jurisdictions, depending on local regulations.
If someone pays you, you can choose multiple wallet addresses. Doing so can isolate each of your transactions so that they cannot be linked. The person paying you will not see your other Bitcoin addresses, nor will they know how you use them.