Take a look at swimming costumes over time.
The thing about microgravity is that it's relative pull by comparison to the atmosphere would be similar to that which we currently experience diving - that is to say that water is quite dense, and we float in it because the pull of gravity affects the water more than us because its denser. We compensate for that by putting on weights, but that is for another topic.
The important factor here is that the way objects like our clothes are going to react around us in microgravity is similar to how they react around us in the water.
So - skirts, T-shirts and other items that are designed to hang loosely are definitely out because they won't hang, or will take much longer to do so, especially in response to our sudden movements. That's why our swimwear looks so much different.
Ultimately, how 'modest' our clothing will need to be will be determined by temperature in the first instance - it's no surprise that European visitors to Polynesian and Southern African areas were shocked by what the inhabitants wore. They came from cold climates, but the locals had adapted their cultures to the humidity and warmth. Add to that, there is no doubt a need to get in and out of clothes as conveniently as possible, and several trends are likely to emerge;
1) Swimsuit Style Apparel. What I mean by this is things like boardshorts, possibly speedos and one pieces, probably some form of shirt that has elastic around the bottom of the shirt to keep it in place at all times, and possibly some of the long-john style swimwear from the Victorian era, especially for formal occasions. Shoes, especially on a space station, will be essentially velcroed extensions of the foot, allowing for good purchase when moving about.
2) Wetsuit Looking Outfits. Neoprene is unlikely to be used in space because wetsuits can be really hard to get in and out of, and getting purchase on the suit is hard enough in full gravity. But, it would make sense that some form of thick (but softer) insulating material would form full body (or more likely 2-piece) coveralls for people on space stations so the internal temperatures don't need to be set so high (preserving energy). See more detail below discussing temperature control in space; short version is that cooling is probably the bigger issue in space in most configurations.
3) Lots of Zippered Pockets. It's not just the human that suffers when clothing needs to be designed for microgravity - it's the things he or she carries around as well. Some things, like wallets, pens, phones, etc. may easily drift out of pockets designed for larger items, meaning that the best and most logical approach is to either button them down or zip them up. Either way, flashier buttons or zips on pockets will become a fashion statement, just like all those extra buttons on suit sleeves that don't actually do anything. Some clothing may eventually manifest buttons and zips in areas that don't actually have pockets, especially for formal wear.
In the end, modesty will initially restrict things like skirts, but practicality is likely to enforce a sense of modesty, by forcing people to stay warm via their own body heat rather than energy taken from the station to stay warm. On the other hand, in an environment where the space station (assumption on my part) actually exists in a close solar orbit or has some other reason for having trouble expelling heat (often the case in current tech spacecraft and stations) then it's more likely to see people in space wearing one piece swimsuit style clothes and boardshorts as a reaction to the warmer environment.
The key things to consider when extrapolating all this is;
Form follows Function - people will dress for comfort and practicality first, then the culture will adopt local mores from these constraints rather than the other way around.
Convenience Always Wins - People simply won't go from convenient clothes (to both wear and put on) to inconvenient. Convenience always improves over time.
Fashion is about Affectation - Things like flashy zippers and buttons will manifest after they prove their usefulness. Ties were originally neckerchiefs that were used to wipe the blood off swords after a duel, but became a bragging item (look how many times I've had to clean off my sword) that led to universal adoption and even generated a few sayings, like someone 'earning their stripes'. Lanyards worn by many military officers were originally used to hold the firing pins for the cannons they commanded, but became a more ornate feature of uniforms much later.
If you factor all this in, I'd expect to see some form of clothing that is at least reminiscent of swimwear from some period of history, with flashy buttons and zippers used for formal attire. As for how modest the clothing remains or changes to, that will literally be set by the thermostat on the station itself.
From comments, there is always going to be debate about the origin of sayings, and the nature of specific clothing affectation. Many of the comments below represent some known variances on the thinking around the introduction of ties and sayings like earning stripes. The statements I make above in that regard should not be considered definitive; they are one of many interpretations of these origins. They are included here because they are relevant possibilities
