I've chosen the Rails Josephine Black Gingham Shirt to layer over the four different outfits. What I love about this shirt is how lightweight and soft it is. Made of 100% rayon, rayon is a semi-synthetic fabric made from cotton, wood pulp, and other natural or synthetic fibers. Rayon has an inherent drape that gives this shirt a more feminine silhouette. While not as breathable as cotton, rayon is still a good choice in the summer as it dries quickly and doesn't trap heat. If you already have a cotton button down in your closet, that would also make a good choice as a layering piece, given cotton's breathability. While this particular pattern is no longer available, Rails does make the Josephine Shirt in other colors and patterns. Here's a link to one in a vertical stripe. For a more casual look, I've left the shirt open. To create a longer leg line, I've knotted the shirt at the natural waist when paired with the jeans and the dress. For a more professional look, I've partly buttoned the shirt and tucked it in when worn with the skirt. 

I love me a blazer, even in the summertime. I've chosen the Slub Modern Blazer from LOFT to layer over the dress and tank/skirt outfit. Made of a cotton/rayon blend, I'm again selecting a layering piece that has a high degree of breathability. I've styled the white blazer in three different ways: 1.) Open with a popped collar and rolled sleeves, 2.) Closed with rolled sleeves and belted, 3.) Open with pushed up sleeves. It's not only stylish but also practical to roll or push up the sleeves on your lightweight blazer when worn in the warm weather. 

I've selected LOFT's Seersucker Tailored Blazer to layer over the tank/shorts and tank/jeans outfits. Seersucker is generally made from a cotton blend (this one is 98% cotton and 2% elastane) and is known for being durable, lightweight, and breathable. Because of how it's woven, seersucker inherently has a puckered appearance in some places. This puckering allows for the trapping of tiny air pockets near the body to keep you cooler. Note that the contrast of the casual base outfit with the more structured blazer elevates the outfit as a whole while keeping it from looking too formal. I'd like to call it "effortless chic". When paired over the tank and shorts, you're now ready to go from the beach to dinner out. When paired over the tank/jeans, you can transition from running errands to a Zoom call or Sunday brunch in seconds. 
 

A kimono is a great casual option for layering, especially for those with more of a boho style, and can be especially versatile when packing for a summer vacation as it works well as a beach cover up. Here I've paired it over the tank/shorts and tank/jeans outfits. Wear it open or belted depending on whether you want a more casual or dressier look.  Kimonos are likely to be made from rayon or polyester as the soft, drapey quality of both fabrics lends itself well to the fluid look of the kimono. Note that polyester is not the best choice to wear outside in very hot weather as it is not breathable. However, it would work well if you're sitting inside in the air conditioning after spending time in the sweltering heat. I purchased the kimono that I'm wearing several seasons ago. You can find something similar on Amazon here.  

When looking for the perfect lightweight summer sweater, stick with a cardigan made from fabrics like cotton, linen, silk, bamboo, and various types of rayon, such as modal and tencel, that are breathable. It's also best to select sweaters in lighter colors that reflect the heat to keep you cooler.  The two sweaters I'm wearing below are both made from viscose, another type of rayon. Furthermore, I suggest a shorter sweater for the summer that ends no lower than halfway between your natural waist and the widest part of your hips. Here I've added a red sweater over the tank/shorts and tank/jeans to add a pop of color and create visual interest to a neutral monochromatic look. I chose to tuck in the sweater to create a longer leg line and a more polished look in the tank/skirt outfit. I added a thin gold belt at the natural waist to create a defined waist and longer leg line when layering the open sweater over the dress. While I purchased these sweaters last year at Ann Taylor, they are currently offering a linen blend short open cardigan that would be a good layering option.

No matter the time of year, you can never go wrong with a lightweight cashmere shawl.  My absolute favorite is the Featherweight Cashmere Silk Frayed Edge Scarf from Quince, which is 60% cashmere and 40% silk. While most people think about wearing cashmere in the winter, cashmere is temperature regulating and will keep you cool in the summertime. It's also a breathable and odor resistant natural fiber. Here I've draped it over my shoulders in three different ways: 1.) Keeping the long layers in front when paired over the tank and jeans, 2.) Wrapping the shawl around my upper arms but keeping the ends loose when paired over the tank/skirt, 3.) Wrapping the shawl around my upper arms and tying the ends loosely behind my back when worn over the dress.