Petticoats, petticoats.... Well, the first rule is
NO SQUAREDANCING PETTICOATS
There's not suited to lolita because they're designed for dancing, which means that they move every time that you do. Lolita skirts are not supposed to swish about.
A Squaredancing petti looks like this:
LinkThe best example that I can give of a Good Petti would be the infamous ITS pettis:
HereAs you can see, they don't look 'swishy' and can support the skirts well. The Poof petticoat has the classic bell shape and even the princess petticoat doesn't have the flaring triangle look that the squaredancing one has.
There is a reason why these two are a cult product.
That's all I have and I'm no expert but I tried!
How'd I do?