Often, when people think of the ragtime era, they think of the music that defined the generation, and although that is certainly a major factor, the era also helped to define a culture in clothing as well.
Because the ragtime era began in the late 19th century and transitioned into the early 20th century (approximately 1897-1918), it also took place during what is known as "the turn of the century". This was also one of the first observations of class divisions. The difference between upper class and lower class citizens could clearly be seen. Much of this had to do with their clothing and how they carried themselves in public. 
The upper class could afford to dress well. Women often appeared in long white gowns, which were in fashion at the time. On these dresses were white collars and usually a brooch that kept the collar closed. Women often wore large white hats and carried parasols as accessories. Bustles were commonplace for women as well. Men often wore light, form-fitting suits and wore bow ties as accessories. It was not rare to see men wearing handlebar mustaches.
Whereas the upper class were put together and proper, and everything was crisp, clean, and uniformed, the immigrant population was quite the opposite. This was the very beginning of immigrants being allowed to enter the United States via Ellis Island. Because they were able to carry very little over to the New World, they had little clothing and little money to buy more when their clothes started to wear out. They would therefore mismatch their clothing or reuse the fabric from an old article of clothing so that they could get multiple uses out of each garment.
Many African Americans enjoyed the popular music from the ragtime era. Their sense of style in clothing seemed to reflect this. Whereas the mostly Caucasian American upper class dressed in clean and light colored fabric (often cream or white), the African Americans dressed in bright and vibrant clothing when they attended clubs that played ragtime music. Whereas the upper class clothing was form-fitting, their clothes were loose, which allowed for free and easy movement. Women often adorned their hair with colorful flowers as accessories, and men often wore vests and bowler hats as their accessories.