Now that you're a member of the Builders Club and have prepared to join the trading frenzy, access Roblox as you would normally. Make sure you have enabled trading by going to your Roblox account, looking underneath your personal blurb, and verifying you are open to trade in the "Trade Accessibility" drop-down menu. You can only trade with members of the Builders Club who are both open to trade and have also set trade-parameters to include you. You may initiate a trade with any person who meets these criteria. If you know the username of someone you would like to trade with, you can access that person's profile by searing the user name in the search box at the top of the Roblox homepage. Next to the "Send Message" option should be a drop-down menu entitled "More." In this menu, "Trade Items" should be available, and selecting this will open the Trade Browser Window. Maybe you have a surplus of Robux and want to use these instead of trading a rare item, or maybe it's the other way around. You can adjust your trade offer until you find a good exchange. Be warned that the market fee for trading R$ is 30%. The total R$ calculated will include this 30% reduction. Now that you're in the trade window, all of your limited items and all of the limited items of the user you are trading to should be displayed. These can be added to a trade with a click. You can remove mis-queued items for trade by hovering your cursor over that item in the current offer window and clicking the "Remove" button that should appear there.  You can also initiate a trade from a user's inventory list, where you should find a button towards the bottom that reads: "Trade Items". The amount of Robux you use cannot go over 50% the current offer, which is calculated in-game. As an example, if your current trade is rated at R$300, you cannot add more than R$150. Submitting a trade will notify the user with whom you are trading with a private message including your offer. Most traders like to receive higher Recent Average Price (RAP) when trading....

TL;DR in Indonesian:
Masuklah (login) ke Roblox. Carilah anggota Builders Club yang juga ingin melakukan perdagangan. Buka jendela peramban perdagangan (trade browser) melalui profil pengguna. Lakukan jual beli sesuka hati. Lakukan penawaran. Lihat dan amati penawaran jual belinya. Bersabarlah.