I am going to participate in "Sew Through The Decades" on Max California's blog aka "Queen of The Trailer Park" She was inspired by the same challenge over at A Lemon Squeezy Home last year.
First up is 1900-1909 from Jan 16- Jan 22 - 1900-1909. As I do want to make something that someone will actually wear, I plan on using some of the following for inspiration to come up with a modernized version, although I have not decided for sure what I will make. If nothing else, could adapt to make Barbie clothes for future grandchildren.
What I Found which features vintage ads and patterns.
From other searches it seems like cinched waists, corsets, puffy sleeves, gored skirts and scalloped edges were in fashion.
A Lemon Squeezy Home came up with the above cute scalloped little girls skirt for her challenge last year
1903 Nine Gored Skirt over at Vintage Pattern Lending Library
Here are some 1909 aprons for under "working clothes on Wikipedia
Max California posted that she will be focusing mainly on mens fashions for this challenge to see her post click here. I plan on figuring out by this weekend what to make and start working on it and will post what I make when I am done.