Pull back the husks of the corn slightly, just enough to check if the corn is okay inside.
Place the corn into a container and cover with water completely. Let the corn soak for 3-4 hours, or even all day if you want to prepare it in the morning
Preheat your BBQ grill to 350 °F.
Place the corn, with the husks still on, onto the grill. Cook, turning every 5 minutes or so, for 30 minutes or until the corn is tender inside. The outside will char, that is normal and fine!
Remove and let cool enough to handle safely, then remove the husks. (they will still be hot inside be careful). If desired, return the corn cobs to the grill and grill them until charred on some of the kernels.