When you post your half of an art trade, linking to the other person's half—or, if it hasn't been posted yet, updating the description once it has. There have been several times lately where I saw something labeled as an art trade and was like, Huh, I wonder what the other artist drew in return and then I head to their gallery and I just... have no idea what to even look for. I suspect it's often not even on here, because so many people use some other site as their main site and then forget to crosspost like half the time.

I have almost no art trades in my gallery personally, but I just now went and updated a 15-year-old post with a cross-link for the heck of it.