Make sure the container is large enough to accommodate the entire pot, all the way to the rim. If the rim of the pot is not covered by water, add more. It's all right if water covers some of the foliage. You may need to weigh down the pot with a brick or a stone to keep it from floating to the surface. Keep the plant in the container until bubbles stop rising from the soil.
Bubbles indicate air pockets in the root ball.
Keep the plant in the water for at least a half hour after the bubbles stop, to assure that the soil is completely saturated. Remove the pot from the container and allow the plant to drain. Place the potted plant inside a large plastic bag and close it tightly. This step will provide much-needed humidity to the foliage while the roots go back into action. Keep the bagged plant in a shady area.