Make X amount of accounts. Purchase premium unlimited auth bot. Bot responsibly. Create new accounts to replace the old when your accounts get banned. Come up with a system to safely transfer gold off to another account. Rinse and repeat. If your desired method involves getting XP i'd also recommend selling the account once it reaches 90+, or 99. Sure it'll be getting X item faster but a 99 stat account goes for enough as is y'know?
KMJT probably goes into much more depth -- "safely transfer gold off" = guide to safe RWT
"mass goldfarming guide" = KMJT's knowledge of VPNs, scripting, etc.
If you really want to get serious about it I'd purchase the guide or do a LOT of googling. Information on the topic isn't hard to find. If you're new to it expect to incur a lot of bans.