Steaming food is not as common as simmering and quick boiling.
It is a good technique for ingredients that are quite delicate and may disintegrate with agitation, for instance, fish. It is also how restaurants keep their soups hot but not overcooked. By placing the soup bowls in a gigantic steamer.
Cooking with steam is a little like double-boiling except it does not need a ceramic double boiling jar and the container is not half-submerged in the water of the bigger pot.
The ingredients and the soup is placed in a soup bowl which can be ceramic or enamel, uncovered. The bowl is then placed in a big pot above boiling water and steamed. The pot can be a big wok or a big stock pot.
Soups can also be steamed in a tiered steamer like this Joyce Chen J26-0054 6-Quart 3-Tier Chinese Steamer.
This reminds me of the huge 3-tier food steamer that my paternal grandmother had. She used it to steam all sort of yummy food. She rarely use it to make soup because our family-sized soup bowl does not fit into it. But she could have separate the soup into petite bowls that do fit.
My grandmother used to use a small dish as a base for the soup bowl to sit on above the boiling water. But there is a small kitchen tool known as a steam rack that is designed just for this.
It is known as a steam rack or steaming stand. It is usually made of metal, with 3 legs. There are varying sizes to suit the size and depths of your pots. If you do a lot of cooking with steam, a steam rack is a more convenient and safer tool than a dish. Chinese grocery shops or supermarkets should stock these. I found a few at Amazon too.
Oven gloves is a logical choice. But I am eager to introduce the plate grabber or plate retriever tongs. It can have 2 or 3 arms. Here's a 2-arm version at Amazon. It is Helen Chen's Asian Kitchen Stainless Steel Plate Retriever Tongs.
This next one hails from Korea and is translated as hot plate forceps (;P). It is available from Qoo10.sg and it ships worldwide.
I hope all this talk about kitchen tools had not dampened your interest to try steaming a soup. Remember, placing small bowls of soups in a steamer is also a good way to keep the soup warm without overcooking it.