We can, of course, look into a corset to give us the shape we need, but sometimes, that can be a disaster - if it is not done up tight enough or if too tight we can end up with bulges in the wrong place.
There are of course some petticoat-type slips on the market that help give a general smooth line, holding in the tummy slightly, however, these are far from pretty and glam. These are usually made of an elastane-type material. There are also tights that are supposed to hold in the tummy.